How to get a F5 BIG-IP VE Developer Lab License
(applies to BIG-IP TMOS Edition) To assist DevOps teams improve their development for the BIG-IP platform, F5 offers a low cost developer lab license.This license can be purchased from your authorized F5 vendor. If you do not have an F5 vendor, you can purchase a lab license online: CDW BIG-IP Virtual Edition Lab License CDW Canada BIG-IP Virtual Edition Lab License Once completed, the order is sent to F5 for fulfillment and your license will be delivered shortly after via e-mail. F5 is investigating ways to improve this process. To download the BIG-IP Virtual Edition, please log into downloads.f5.com (separate login from DevCentral), and navigate to your appropriate virtual edition, example: For VMware Fusion or Workstation or ESX/i:BIGIP-16.1.2-0.0.18.ALL-vmware.ova For Microsoft HyperV:BIGIP-16.1.2-0.0.18.ALL.vhd.zip KVM RHEL/CentoOS: BIGIP-16.1.2-0.0.18.ALL.qcow2.zip Note: There are also 1 Slot versions of the above images where a 2nd boot partition is not needed for in-place upgrades. These images include_1SLOT- to the image name instead of ALL. The below guides will help get you started with F5 BIG-IP Virtual Edition to develop for VMWare Fusion, AWS, Azure, VMware, or Microsoft Hyper-V. These guides follow standard practices for installing in production environments and performance recommendations change based on lower use/non-critical needs fo Dev/Lab environments. Similar to driving a tank, use your best judgement. DeployingF5 BIG-IP Virtual Edition on VMware Fusion Deploying F5 BIG-IP in Microsoft Azure for Developers Deploying F5 BIG-IP in AWS for Developers Deploying F5 BIG-IP in Windows Server Hyper-V for Developers Deploying F5 BIG-IP in VMware vCloud Director and ESX for Developers Note: F5 Support maintains authoritativeAzure, AWS, Hyper-V, and ESX/vCloud installation documentation. VMware Fusion is not an official F5-supported hypervisor so DevCentral publishes the Fusion guide with the help of our Field Systems Engineering teams.
Controlling a Pool Members Ratio and Priority Group with iControl
A Little Background A question came in through the iControl forums about controlling a pool members ratio and priority programmatically. The issue really involves how the API’s use multi-dimensional arrays but I thought it would be a good opportunity to talk about ratio and priority groups for those that don’t understand how they work. In the first part of this article, I’ll talk a little about what pool members are and how their ratio and priorities apply to how traffic is assigned to them in a load balancing setup. The details in this article were based on BIG-IP version 11.1, but the concepts can apply to other previous versions as well. Load Balancing In it’s very basic form, a load balancing setup involves a virtual ip address (referred to as a VIP) that virtualized a set of backend servers. The idea is that if your application gets very popular, you don’t want to have to rely on a single server to handle the traffic. A VIP contains an object called a “pool” which is essentially a collection of servers that it can distribute traffic to. The method of distributing traffic is referred to as a “Load Balancing Method”. You may have heard the term “Round Robin” before. In this method, connections are passed one at a time from server to server. In most cases though, this is not the best method due to characteristics of the application you are serving. Here are a list of the available load balancing methods in BIG-IP version 11.1. Load Balancing Methods in BIG-IP version 11.1 Round Robin: Specifies that the system passes each new connection request to the next server in line, eventually distributing connections evenly across the array of machines being load balanced. This method works well in most configurations, especially if the equipment that you are load balancing is roughly equal in processing speed and memory. Ratio (member): Specifies that the number of connections that each machine receives over time is proportionate to a ratio weight you define for each machine within the pool. Least Connections (member): Specifies that the system passes a new connection to the node that has the least number of current connections in the pool. This method works best in environments where the servers or other equipment you are load balancing have similar capabilities. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the current number of connections per node or the fastest node response time. Observed (member): Specifies that the system ranks nodes based on the number of connections. Nodes that have a better balance of fewest connections receive a greater proportion of the connections. This method differs from Least Connections (member), in that the Least Connections method measures connections only at the moment of load balancing, while the Observed method tracks the number of Layer 4 connections to each node over time and creates a ratio for load balancing. This dynamic load balancing method works well in any environment, but may be particularly useful in environments where node performance varies significantly. Predictive (member): Uses the ranking method used by the Observed (member) methods, except that the system analyzes the trend of the ranking over time, determining whether a node's performance is improving or declining. The nodes in the pool with better performance rankings that are currently improving, rather than declining, receive a higher proportion of the connections. This dynamic load balancing method works well in any environment. Ratio (node): Specifies that the number of connections that each machine receives over time is proportionate to a ratio weight you define for each machine across all pools of which the server is a member. Least Connections (node): Specifies that the system passes a new connection to the node that has the least number of current connections out of all pools of which a node is a member. This method works best in environments where the servers or other equipment you are load balancing have similar capabilities. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the number of current connections per node, or the fastest node response time. Fastest (node): Specifies that the system passes a new connection based on the fastest response of all pools of which a server is a member. This method might be particularly useful in environments where nodes are distributed across different logical networks. Observed (node): Specifies that the system ranks nodes based on the number of connections. Nodes that have a better balance of fewest connections receive a greater proportion of the connections. This method differs from Least Connections (node), in that the Least Connections method measures connections only at the moment of load balancing, while the Observed method tracks the number of Layer 4 connections to each node over time and creates a ratio for load balancing. This dynamic load balancing method works well in any environment, but may be particularly useful in environments where node performance varies significantly. Predictive (node): Uses the ranking method used by the Observed (member) methods, except that the system analyzes the trend of the ranking over time, determining whether a node's performance is improving or declining. The nodes in the pool with better performance rankings that are currently improving, rather than declining, receive a higher proportion of the connections. This dynamic load balancing method works well in any environment. Dynamic Ratio (node) : This method is similar to Ratio (node) mode, except that weights are based on continuous monitoring of the servers and are therefore continually changing. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the number of current connections per node or the fastest node response time. Fastest (application): Passes a new connection based on the fastest response of all currently active nodes in a pool. This method might be particularly useful in environments where nodes are distributed across different logical networks. Least Sessions: Specifies that the system passes a new connection to the node that has the least number of current sessions. This method works best in environments where the servers or other equipment you are load balancing have similar capabilities. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the number of current sessions. Dynamic Ratio (member): This method is similar to Ratio (node) mode, except that weights are based on continuous monitoring of the servers and are therefore continually changing. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the number of current connections per node or the fastest node response time. L3 Address: This method functions in the same way as the Least Connections methods. We are deprecating it, so you should not use it. Weighted Least Connections (member): Specifies that the system uses the value you specify in Connection Limit to establish a proportional algorithm for each pool member. The system bases the load balancing decision on that proportion and the number of current connections to that pool member. For example,member_a has 20 connections and its connection limit is 100, so it is at 20% of capacity. Similarly, member_b has 20 connections and its connection limit is 200, so it is at 10% of capacity. In this case, the system select selects member_b. This algorithm requires all pool members to have a non-zero connection limit specified. Weighted Least Connections (node): Specifies that the system uses the value you specify in the node's Connection Limitand the number of current connections to a node to establish a proportional algorithm. This algorithm requires all nodes used by pool members to have a non-zero connection limit specified. Ratios The ratio is used by the ratio-related load balancing methods to load balance connections. The ratio specifies the ratio weight to assign to the pool member. Valid values range from 1 through 100. The default is 1, which means that each pool member has an equal ratio proportion. So, if you have server1 a with a ratio value of “10” and server2 with a ratio value of “1”, server1 will get served 10 connections for every one that server2 receives. This can be useful when you have different classes of servers with different performance capabilities. Priority Group The priority group is a number that groups pool members together. The default is 0, meaning that the member has no priority. To specify a priority, you must activate priority group usage when you create a new pool or when adding or removing pool members. When activated, the system load balances traffic according to the priority group number assigned to the pool member. The higher the number, the higher the priority, so a member with a priority of 3 has higher priority than a member with a priority of 1. The easiest way to think of priority groups is as if you are creating mini-pools of servers within a single pool. You put members A, B, and C in to priority group 5 and members D, E, and F in priority group 1. Members A, B, and C will be served traffic according to their ratios (assuming you have ratio loadbalancing configured). If all those servers have reached their thresholds, then traffic will be distributed to servers D, E, and F in priority group 1. he default setting for priority group activation is Disabled. Once you enable this setting, you can specify pool member priority when you create a new pool or on a pool member's properties screen. The system treats same-priority pool members as a group. To enable priority group activation in the admin GUI, select Less than from the list, and in the Available Member(s) box, type a number from 0 to 65535 that represents the minimum number of members that must be available in one priority group before the system directs traffic to members in a lower priority group. When a sufficient number of members become available in the higher priority group, the system again directs traffic to the higher priority group. Implementing in Code The two methods to retrieve the priority and ratio values are very similar. They both take two parameters: a list of pools to query, and a 2-D array of members (a list for each pool member passed in). long [] [] get_member_priority( in String [] pool_names, in Common__AddressPort [] [] members ); long [] [] get_member_ratio( in String [] pool_names, in Common__AddressPort [] [] members ); The following PowerShell function (utilizing the iControl PowerShell Library), takes as input a pool and a single member. It then make a call to query the ratio and priority for the specific member and writes it to the console. function Get-PoolMemberDetails() { param( $Pool = $null, $Member = $null ); $AddrPort = Parse-AddressPort $Member; $RatioAofA = (Get-F5.iControl).LocalLBPool.get_member_ratio( @($Pool), @( @($AddrPort) ) ); $PriorityAofA = (Get-F5.iControl).LocalLBPool.get_member_priority( @($Pool), @( @($AddrPort) ) ); $ratio = $RatioAofA[0][0]; $priority = $PriorityAofA[0][0]; "Pool '$Pool' member '$Member' ratio '$ratio' priority '$priority'"; } Setting the values with the set_member_priority and set_member_ratio methods take the same first two parameters as their associated get_* methods, but add a third parameter for the priorities and ratios for the pool members. set_member_priority( in String [] pool_names, in Common::AddressPort [] [] members, in long [] [] priorities ); set_member_ratio( in String [] pool_names, in Common::AddressPort [] [] members, in long [] [] ratios ); The following Powershell function takes as input the Pool and Member with optional values for the Ratio and Priority. If either of those are set, the function will call the appropriate iControl methods to set their values. function Set-PoolMemberDetails() { param( $Pool = $null, $Member = $null, $Ratio = $null, $Priority = $null ); $AddrPort = Parse-AddressPort $Member; if ( $null -ne $Ratio ) { (Get-F5.iControl).LocalLBPool.set_member_ratio( @($Pool), @( @($AddrPort) ), @($Ratio) ); } if ( $null -ne $Priority ) { (Get-F5.iControl).LocalLBPool.set_member_priority( @($Pool), @( @($AddrPort) ), @($Priority) ); } } In case you were wondering how to create the Common::AddressPort structure for the $AddrPort variables in the above examples, here’s a helper function I wrote to allocate the object and fill in it’s properties. function Parse-AddressPort() { param($Value); $tokens = $Value.Split(":"); $r = New-Object iControl.CommonAddressPort; $r.address = $tokens[0]; $r.port = $tokens[1]; $r; } Download The Source The full source for this example can be found in the iControl CodeShare under PowerShell PoolMember Ratio and Priority.BigIP Report Old
Problem this snippet solves: This codeshare has been deprecated due to a hosting platform corruption. I have movedcode and conversation to a new record (on the same original URL) https://devcentral.f5.com/s/articles/bigip-report can be Overview This is a script which will generate a report of the BigIP LTM configuration on all your load balancers making it easy to find information and get a comprehensive overview of virtual servers and pools connected to them. This information is used to relay information to our NOC and developers to give them insight in where things are located and to be able to plan patching and deploys. I also use it myself as a quick way get information or gather data used as a foundation for RFC's, ie get a list of all external virtual servers without compression profiles. The script has been running on 13 pairs of load balancers, indexing over 1200 virtual servers for several years now and the report is widely used across the company and by many companies and governments across the world. It's easy to setup and use and only requires guest permissions on your devices. Demo/Preview Please note that it takes time to make these so sometimes they're a bit outdated and they only cover one HA pair. However, they still serve the purpose of showing what you can expect from the report. Interactive demo http://loadbalancing.se/bigipreportdemo/ Screen shots The main report: The device overview: Certificate details: How to use this snippet: This codeshare has been deprecated due to a hosting platform corruption. I have movedcode and conversation to a new record (on the same original URL) https://devcentral.f5.com/s/articles/bigip-report Installation instructions BigipReport REST This is the only branch we're updating since middle of 2020 and it supports 12.x and upwards (maybe even 11.6). Download:https://loadbalancing.se/downloads/bigipreport-v5.5.4.zip Documentation, installation instructions and troubleshooting:https://loadbalancing.se/bigipreport-rest/ Docker support This will be the recommended way of running bigipreport in the near future. It's still undergoing testing but it's looking really good so far. https://loadbalancing.se/2021/01/05/running-bigipreport-on-docker/ BigipReport (Legacy) Older version of the report that only runs on Windows and is depending on a Powershell plugin originally written by Joe Pruitt (F5). BigipReport (Stable): https://loadbalancing.se/downloads/bigipreport-5.3.1.zip BigipReport (BETA): https://loadbalancing.se/downloads/bigipreport-5.4.0-beta.zip iControl Snapin: https://loadbalancing.se/downloads/f5-icontrol.zip Documentation and installation instructions: https://loadbalancing.se/bigip-report/ Upgrade instructions Protect the report using APM and active directory Written by DevCentral member Shann_P: https://loadbalancing.se/2018/04/08/protecting-bigip-report-behind-an-apm-by-shannon-poole/ Got issues/problems/feedback? Still have issues? Drop a comment below. We usually reply quite fast. Any bugs found, issues detected or ideas contributed makes the report better for everyone, so it's always appreciated. --- Also trying out a Discord channel now. You're welcome to hang out with us there: https://discord.gg/7JJvPMYahA Code : 85931,86647,90730 Tested this on version: 13.0
F5 iApp Automated Backup
Problem this snippet solves: This is now available on GitHub! Please look on GitHub for the latest version, and submit any bugs or questions as an "Issue" on GitHub: (Note: DevCentral admin update - Daniel's project appears abandoned so it's been forked and updated to the link below. @damnski on github added some SFTP code that has been merged in as well.) https://github.com/f5devcentral/f5-automated-backup-iapp Intro Building on the significant work of Thomas Schockaert (and several other DevCentralites) I enhanced many aspects I needed for my own purposes, updated many things I noticed requested on the forums, and added additional documentation and clarification. As you may see in several of my comments on the original posts, I iterated through several 2.2.x versions and am now releasing v3.0.0. Below is the breakdown! Also, I have done quite a bit of testing (mostly on v13.1.0.1 lately) and I doubt I've caught everything, especially with all of the changes. Please post any questions or issues in the comments. Cheers! Daniel Tavernier (tabernarious) Related posts: Git Repository for f5-automated-backup-iapp (https://github.com/tabernarious/f5-automated-backup-iapp) https://community.f5.com/t5/technical-articles/f5-automated-backups-the-right-way/ta-p/288454 https://community.f5.com/t5/crowdsrc/complete-f5-automated-backup-solution/ta-p/288701 https://community.f5.com/t5/crowdsrc/complete-f5-automated-backup-solution-2/ta-p/274252 https://community.f5.com/t5/technical-forum/automated-backup-solution/m-p/24551 https://community.f5.com/t5/crowdsrc/tkb-p/CrowdSRC v3.2.1 (20201210) Merged v3.1.11 and v3.2.0 for explicit SFTP support (separate from SCP). Tweaked the SCP and SFTP upload directory handling; detailed instructions are in the iApp. Tested on 13.1.3.4 and 14.1.3 v3.1.11 (20201210) Better handling of UCS passphrases, and notes about characters to avoid. I successfully tested this exact passphrase in the 13.1.3.4 CLI (surrounded with single quote) and GUI (as-is): `~!@#$%^*()aB1-_=+[{]}:./? I successfully tested this exact passphrase in 14.1.3 (square-braces and curly-braces would not work): `~!@#$%^*()aB1-_=+:./? Though there may be situations these could work, avoid these characters (separated by spaces): " ' & | ; < > \ [ ] { } , Moved changelog and notes from the template to CHANGELOG.md and README.md. Replaced all tabs (\t) with four spaces. v3.1.10 (20201209) Added SMB Version and SMB Security options to support v14+ and newer versions of Microsoft Windows and Windows Server. Tested SMB/CIFS on 13.1.3.4 and 14.1.3 against Windows Server 2019 using "2.0" and "ntlmsspi" v3.1.0: Removed "app-service none" from iCall objects. The iCall objects are now created as part of the Application Service (iApp) and are properly cleaned up if the iApp is redeployed or deleted. Reasonably tested on 11.5.4 HF2 (SMB worked fine using "mount -t cifs") and altered requires-bigip-version-min to match. Fixing error regarding "script did not successfully complete: (can't read "::destination_parameters__protocol_enable": no such variable" by encompassing most of the "implementation" in a block that first checks $::backup_schedule__frequency_select for "Disable". Added default value to "filename format". Changed UCS default value for $backup_file_name_extension to ".ucs" and added $fname_noext. Removed old SFTP sections and references (now handled through SCP/SFTP). Adjusted logging: added "sleep 1" to ensure proper logging; added $backup_directory to log message. Adjusted some help messages. New v3.0.0 features: Supports multiple instances! (Deploy multiple copies of the iApp to save backups to different places or perhaps to keep daily backups locally and send weekly backups to a network drive.) Fully ConfigSync compatible! (Encrypted values now in $script instead of local file.) Long passwords supported! (Using "-A" with openssl which reads/writes base64 encoded strings as a single line.) Added $script error checking for all remote backup types! (Using 'catch' to prevent tcl errors when $script aborts.) Backup files are cleaned up after any $script errors due to new error checking. Added logging! (Run logs sent to '/var/log/ltm' via logger command which is compatible with BIG-IP Remote Logging configuration (syslog). Run logs AND errors sent to '/var/tmp/scriptd.out'. Errors may include plain-text passwords which should not be in /var/log/ltm or syslog.) Added custom cipher option for SCP! (In case BIG-IP and the destination server are not cipher-compatible out of the box.) Added StrictHostKeyChecking=no option. (This is insecure and should only be used for testing--lots of warnings.) Combined SCP and SFTP because they are both using SCP to perform the remote copy. (Easier to maintain!) Original v1.x.x and v2.x.x features kept (copied from an original post): It allows you to choose between both UCS or SCF as backup-types. (whilst providing ample warnings about SCF not being a very good restore-option due to the incompleteness in some cases) It allows you to provide a passphrase for the UCS archives (the standard GUI also does this, so the iApp should too) It allows you to not include the private keys (same thing: standard GUI does it, so the iApp does it too) It allows you to set a Backup Schedule for every X minutes/hours/days/weeks/months or a custom selection of days in the week It allows you to set the exact time, minute of the hour, day of the week or day of the month when the backup should be performed (depending on the usefulness with regards to the schedule type) It allows you to transfer the backup files to external devices using 4 different protocols, next to providing local storage on the device itself SCP (username/private key without password) SFTP (username/private key without password) FTP (username/password) SMB (now using TMOS v12.x.x compatible 'mount -t cifs', with username/password) Local Storage (/var/local/ucs or /var/local/scf) It stores all passwords and private keys in a secure fashion: encrypted by the master key of the unit (f5mku), rendering it safe to store the backups, including the credentials off-box It has a configurable automatic pruning function for the Local Storage option, so the disk doesn't fill up (i.e. keep last X backup files) It allows you to configure the filename using the date/time wildcards from the tcl [clock] command, as well as providing a variable to include the hostname It requires only the WebGUI to establish the configuration you desire It allows you to disable the processes for automated backup, without you having to remove the Application Service or losing any previously entered settings For the external shellscripts it automatically generates, the credentials are stored in encrypted form (using the master key) It allows you to no longer be required to make modifications on the linux command line to get your automated backups running after an RMA or restore operation It cleans up after itself, which means there are no extraneous shellscripts or status files lingering around after the scripts execute How to use this snippet: Find and download the latest iApp template on GitHub (e.g "f5.automated_backup.v3.2.1.tmpl.tcl"). Import the text file as an iApp Template in the BIG-IP GUI. Create an Application Service using the imported Template. Answer the questions (paying close attention to the help sections). Check /var/tmp/scriptd.out for general logs and errors. Tested this on version: 16.0
Intro to Load Balancing for Developers – The Algorithms
If you’re new to this series, you can find the complete list of articles in the series on my personal page here If you are writing applications to sit behind a Load Balancer, it behooves you to at least have a clue what the algorithm your load balancer uses is about. We’re taking this week’s installment to just chat about the most common algorithms and give a plain- programmer description of how they work. While historically the algorithm chosen is both beyond the developers’ control, you’re the one that has to deal with performance problems, so you should know what is happening in the application’s ecosystem, not just in the application. Anything that can slow your application down or introduce errors is something worth having reviewed. For algorithms supported by the BIG-IP, the text here is paraphrased/modified versions of the help text associated with the Pool Member tab of the BIG-IP UI. If they wrote a good description and all I needed to do was programmer-ize it, then I used it. For algorithms not supported by the BIG-IP I wrote from scratch. Note that there are many, many more algorithms out there, but as you read through here you’ll see why these (or minor variants of them) are the ones you’ll see the most. Plain Programmer Description: Is not intended to say anything about the way any particular dev team at F5 or any other company writes these algorithms, they’re just an attempt to put the process into terms that are easier for someone with a programming background to understand. Hopefully a successful attempt. Interestingly enough, I’ve pared down what BIG-IP supports to a subset. That means that F5 employees and aficionados will be going “But you didn’t mention…!” and non-F5 employees will likely say “But there’s the Chi-Squared Algorithm…!” (no, chi-squared is theoretical distribution method I know of because it was presented as a proof for testing the randomness of a 20 sided die, ages ago in Dragon Magazine). The point being that I tried to stick to a group that builds on each other in some connected fashion. So send me hate mail… I’m good. Unless you can say more than 2-5% of the world’s load balancers are running the algorithm, I won’t consider that I missed something important. The point is to give developers and software architects a familiarity with core algorithms, not to build the worlds most complete lexicon of algorithms. Random: This load balancing method randomly distributes load across the servers available, picking one via random number generation and sending the current connection to it. While it is available on many load balancing products, its usefulness is questionable except where uptime is concerned – and then only if you detect down machines. Plain Programmer Description: The system builds an array of Servers being load balanced, and uses the random number generator to determine who gets the next connection… Far from an elegant solution, and most often found in large software packages that have thrown load balancing in as a feature. Round Robin: Round Robin passes each new connection request to the next server in line, eventually distributing connections evenly across the array of machines being load balanced. Round Robin works well in most configurations, but could be better if the equipment that you are load balancing is not roughly equal in processing speed, connection speed, and/or memory. Plain Programmer Description: The system builds a standard circular queue and walks through it, sending one request to each machine before getting to the start of the queue and doing it again. While I’ve never seen the code (or actual load balancer code for any of these for that matter), we’ve all written this queue with the modulus function before. In school if nowhere else. Weighted Round Robin (called Ratio on the BIG-IP): With this method, the number of connections that each machine receives over time is proportionate to a ratio weight you define for each machine. This is an improvement over Round Robin because you can say “Machine 3 can handle 2x the load of machines 1 and 2”, and the load balancer will send two requests to machine #3 for each request to the others. Plain Programmer Description: The simplest way to explain for this one is that the system makes multiple entries in the Round Robin circular queue for servers with larger ratios. So if you set ratios at 3:2:1:1 for your four servers, that’s what the queue would look like – 3 entries for the first server, two for the second, one each for the third and fourth. In this version, the weights are set when the load balancing is configured for your application and never change, so the system will just keep looping through that circular queue. Different vendors use different weighting systems – whole numbers, decimals that must total 1.0 (100%), etc. but this is an implementation detail, they all end up in a circular queue style layout with more entries for larger ratings. Dynamic Round Robin (Called Dynamic Ratio on the BIG-IP): is similar to Weighted Round Robin, however, weights are based on continuous monitoring of the servers and are therefore continually changing. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the current number of connections per node or the fastest node response time. This Application Delivery Controller method is rarely available in a simple load balancer. Plain Programmer Description: If you think of Weighted Round Robin where the circular queue is rebuilt with new (dynamic) weights whenever it has been fully traversed, you’ll be dead-on. Fastest: The Fastest method passes a new connection based on the fastest response time of all servers. This method may be particularly useful in environments where servers are distributed across different logical networks. On the BIG-IP, only servers that are active will be selected. Plain Programmer Description: The load balancer looks at the response time of each attached server and chooses the one with the best response time. This is pretty straight-forward, but can lead to congestion because response time right now won’t necessarily be response time in 1 second or two seconds. Since connections are generally going through the load balancer, this algorithm is a lot easier to implement than you might think, as long as the numbers are kept up to date whenever a response comes through. These next three I use the BIG-IP name for. They are variants of a generalized algorithm sometimes called Long Term Resource Monitoring. Least Connections: With this method, the system passes a new connection to the server that has the least number of current connections. Least Connections methods work best in environments where the servers or other equipment you are load balancing have similar capabilities. This is a dynamic load balancing method, distributing connections based on various aspects of real-time server performance analysis, such as the current number of connections per node or the fastest node response time. This Application Delivery Controller method is rarely available in a simple load balancer. Plain Programmer Description: This algorithm just keeps track of the number of connections attached to each server, and selects the one with the smallest number to receive the connection. Like fastest, this can cause congestion when the connections are all of different durations – like if one is loading a plain HTML page and another is running a JSP with a ton of database lookups. Connection counting just doesn’t account for that scenario very well. Observed: The Observed method uses a combination of the logic used in the Least Connections and Fastest algorithms to load balance connections to servers being load-balanced. With this method, servers are ranked based on a combination of the number of current connections and the response time. Servers that have a better balance of fewest connections and fastest response time receive a greater proportion of the connections. This Application Delivery Controller method is rarely available in a simple load balancer. Plain Programmer Description: This algorithm tries to merge Fastest and Least Connections, which does make it more appealing than either one of the above than alone. In this case, an array is built with the information indicated (how weighting is done will vary, and I don’t know even for F5, let alone our competitors), and the element with the highest value is chosen to receive the connection. This somewhat counters the weaknesses of both of the original algorithms, but does not account for when a server is about to be overloaded – like when three requests to that query-heavy JSP have just been submitted, but not yet hit the heavy work. Predictive: The Predictive method uses the ranking method used by the Observed method, however, with the Predictive method, the system analyzes the trend of the ranking over time, determining whether a servers performance is currently improving or declining. The servers in the specified pool with better performance rankings that are currently improving, rather than declining, receive a higher proportion of the connections. The Predictive methods work well in any environment. This Application Delivery Controller method is rarely available in a simple load balancer. Plain Programmer Description: This method attempts to fix the one problem with Observed by watching what is happening with the server. If its response time has started going down, it is less likely to receive the packet. Again, no idea what the weightings are, but an array is built and the most desirable is chosen. You can see with some of these algorithms that persistent connections would cause problems. Like Round Robin, if the connections persist to a server for as long as the user session is working, some servers will build a backlog of persistent connections that slow their response time. The Long Term Resource Monitoring algorithms are the best choice if you have a significant number of persistent connections. Fastest works okay in this scenario also if you don’t have access to any of the dynamic solutions. That’s it for this week, next week we’ll start talking specifically about Application Delivery Controllers and what they offer – which is a whole lot – that can help your application in a variety of ways. Until then! Don.PowerShell module for the F5 LTM REST API
Problem this snippet solves: To report an issue with the F5-LTM or F5-BIGIP modules, please use the Issues sections of the GitHub repos (here and here) instead of commenting here. Thanks! This PowerShell module uses the iControlREST API to manipulate and query pools, pool members, virtual servers, and iRules. It aims to support version 11.5.1 and higher, and to conform to the schedule for technical support of versions, though this may eventually prove to become difficult. The module currently includes some functionality that, strictly speaking, is outside the scope of the LTM module. Hence, there is an active effort to wrap this LTM module into a larger BIG-IP module, and relocate that functionality elsewhere within that parent module, as well as expand the scope of functionality to include BIG-IP DNS (formerly GTM) and possibly other areas. Both the LTM module and the parent BIG-IP module are projects on github. Please use these projects to report any issues you discover. Thanks! The module contains the following functions. Add-iRuleToVirtualServer Add-iRuleToVirtualServer Add-PoolMember Add-PoolMonitor Disable-PoolMember Disable-VirtualServer Enable-PoolMember Enable-VirtualServer Get-CurrentConnectionCount (deprecated; use Get-PoolMemberStats | Select-Object -ExpandProperty 'serverside.curConns') Get-F5Session (will be deprecated in future versions. use New-F5Session) Get-F5Status Get-HealthMonitor Get-HealthMonitorType Get-iRule Get-iRuleCollection (deprecated; use Get-iRule) Get-Node Get-BIGIPPartition Get-Pool Get-PoolList (deprecated; use Get-Pool) Get-PoolMember Get-PoolMemberCollection (deprecated; use Get-PoolMember) Get-PoolMemberCollectionStatus Get-PoolMemberDescription (deprecated; use Get-PoolMember) Get-PoolMemberIP (deprecated; use Get-PoolMember) Get-PoolMembers (deprecated; use Get-PoolMember) Get-PoolMemberStats Get-PoolMemberStatus (deprecated; use Get-PoolMember) Get-PoolMonitor Get-PoolsForMember Get-StatusShape Get-VirtualServer Get-VirtualServeriRuleCollection (deprecated; use Get-VirtualServer | Where rules | Select -ExpandProperty rules) Get-VirtualServerList (deprecated; use Get-VirtualServer) Invoke-RestMethodOverride New-F5Session New-HealthMonitor New-Node New-Pool New-VirtualServer Remove-HealthMonitor Remove-iRule Remove-iRuleFromVirtualServer Remove-Pool Remove-PoolMember Remove-PoolMonitor Remove-ProfileRamCache Remove-Node Remove-VirtualServer Set-iRule Set-PoolLoadBalancingMode (deprecated; use Set-Pool) Set-PoolMemberDescription Set-Pool Set-VirtualServer Sync-DeviceToGroup Test-F5Session Test-Functionality Test-HealthMonitor Test-Node Test-Pool Test-VirtualServer How to use this snippet: To use the module, click 'Download Zip', extract the files, and place them in a folder named F5-LTM beneath your PowerShell modules folder. By default, this is %USERPROFILE%\Documents\WindowsPowerShell\Modules. The WindowsPowerShell and Modules folders may need to be created. You will most likely need to unblock the files after extracting them. Use the Unblock-File PS cmdlet to accomplish this. The Validation.cs class file (based on code posted by Brian Scholer) allows for using the REST API with LTM devices with self-signed SSL certificates. Nearly all of the functions require an F5 session object as a parameter, which contains the base URL for the F5 LTM and a credential object for a user with privileges to manipulate the F5 LTM via the REST API. Use the New-F5session function to create this object. This function expects the following parameters: The name or IP address of the F5 LTM device A credential object for a user with rights to use the REST API An optional TokenLifespan value for extending the life of the authentication token past the default 20 minutes You can create a credential object using Get-Credential and entering the username and password at the prompts, or programmatically like this: $secpasswd = ConvertTo-SecureString "PlainTextPassword" -AsPlainText -Force $mycreds = New-Object System.Management.Automation.PSCredential "username", $secpasswd Thanks to Kotesh Bandhamravuri and his blog entry for this snippet. There is a function called Test-Functionality that takes an F5Session object, a new pool name, a new virtual server, an IP address for the virtual server, and a computer name as a pool member, and validates nearly all the functions in the module. I've also contributed this code sample for how to gather some basic info about your LTM with this PS module. The module has been tested on: 11.5.1 Build 8.0.175 Hotfix 8 and later 11.6.0 Build 5.0.429 Hotfix 4 and later 12.0 / 12.1 13.0 Code : https://github.com/joel74/POSH-LTM-Rest Tested this on version: 11.5Where are F5's archived deployment guides?
Archived F5 Deployment Guides This article contains an index of F5’s archived deployment guides, previously hosted onF5 | Multi-Cloud Security and Application Delivery.They are all now hosted on cdn.f5.com. Archived guides... are no longer supported and no longer being updated -provided for reference only. may refer to products or versions, by F5 or 3rd parties that are end-of-life (EOL) or end-of-support (EOS). may refer to iApp templates that are deprecated. For current/updated iApps and FAST templates see myF5 K13422: F5-supported and F5-contributed iApp templates Current F5 Deployment Guides Deployment Guides (https://www.f5.com/resources/deployment-guides) IMPORTANT:The guidance found in archived guides is no longer supported by F5, Inc. and is supplied for reference only.For assistance configuring F5 devices with 3 rd party applications we recommend contacting F5 Professional Services here:Request Professional Services | F5 Archived Deployment Guide Index Deployment Guide Name (links to off-platform) Written for… CA Bundle Iapp BIG-IP V11.5+, V12.X, V13 Microsoft Internet Information Services 7.0, 7.5, 8.0, 10 BIG-IP V11.4 - V13: LTM, AAM, AFM Microsoft Exchange Server 2016 BIG-IP V11 - V13: LTM, APM, AFM Microsoft Sharepoint 2016 BIG-IP V11.4 - V13: LTM, APM, ASM, AFM, AAM Microsoft Active Directory Federation Services BIG-IP V11 - V13: LTM, APM SAP Netweaver: Erp Central Component BIG-IP V11.4: LTM, AAM, AFM, ASM SAP Netweaver: Enterprise Portal BIG-IP V11.4: LTM, AAM, AFM, ASM Microsoft Dynamics CRM 2013 And 2011 BIG-IP V11 - V13: LTM, APM, AFM IBM Qradar BIG-IP V11.3: LTM Microsoft Dynamics CRM 2016 and 2015 BIG-IP V11 - V13: LTM, APM, AFM SSL Intercept V1.5 BIG-IP V12.0+: LTM IBM Websphere 7 BIG-IP LTM, WEBACCELERATOR, FIREPASS Microsoft Dynamics CRM 4.0 BIG-IP V9.X: LTM SSL Intercept V1.0 BIG-IP V11.4+, V12.0: LTM, AFM SMTP Servers BIG-IP V11.4, V12.X, V13: LTM, AFM Oracle E-Business Suite 12 BIG-IP V11.4 - V13: LTM, AFM, AAM HTTP Applications BIG-IP V11.4 - V13: LTM, AFM, AAM Amazon Web Services Availability Zones BIG-IP LTM VE: V12.1.0 HF2+, V13 Oracle PeopleSoft Enterprise Applications BIG-IP V11.4+: LTM, AAM, AFM, ASM HTTP Applications: Downloadable IApp: BIG-IP V11.4 - V13: LTM, APM, AFM, ASM Oracle Weblogic 12.1, 10.3 BIG-IP V11.4: LTM, AFM, AAM IBM Lotus Sametime BIG-IP V10: LTM Analytics BIG-IP V11.4 - V14.1: LTM, APM, AAM, ASM, AFM Cacti Open Source Network Monitoring System BIG-IP V10: LTM NIST SP-800-53R4 Compliance BIG-IP: V12 Apache HTTP Server BIG-IP V11, V12: LTM, APM, AFM, AAM Diameter Traffic Management BIG-IP V10: LTM Nagios Open Source Network Monitoring System BIG-IP V10: LTM F5 BIG-IP Apm With IBM, Oracle and Microsoft BIG-IP V10: APM Apache Web Server BIG-IP V9.4.X, V10: LTM, WA DNS Traffic Management BIG-IP V10: LTM Diameter Traffic Management BIG-IP V11.4+, V12: LTM Citrix XenDesktop BIG-IP V10: LTM F5 As A SAML 2.0 Identity Provider For Common SaaS Applications BIG-IP V11.3+, V12.0 Apache Tomcat BIG-IP V10: LTM Citrix Presentation Server BIG-IP V9.X: LTM Npath Routing - Direct Server Return BIG-IP V11.4 - V13: LTM Data Center Firewall BIG-IP V11.6+, V12: AFM, LTM Citrix XenApp Or XenDesktop Iapp V2.3.0 BIG-IP V11, V12: LTM, APM, AFM Citrix XenApp Or XenDesktop BIG-IP V10.2.1: APM
How to rewrite a path to a backend service dropping the prefix and passing the remaining path?
Hello, I am not sure whether my posting is appropriate in this area, so please delete it if there is a violation of posting rules... This must be a common task, but I cannot figure out how to do the following fanout rewrite in our nginx ingress: http://abcccc.com/httpbin/anything-> /anything (the httpbin backend service) When I create the following ingress with a path of '/' and send the query, I receive a proper response. curl -I -k http://abczzz.com/anything apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: mikie-ingress namespace: mikie spec: ingressClassName: nginx rules: - host: abczzz.com http: paths: - path: / pathType: Prefix backend: service: name: httpbin-service port: number: 8999 What I really need is to be able to redirect to different services off of this single host, so I changed the ingress to the following, but the query always fails with a 404. Basically, I want the /httpbin to disappear and pass the path onto the backend service, httpbin. curl -I -k http://abczzz.com/httpbin/anything apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: mikie-ingress namespace: mikie annotations: nginx.ingress.kubernetes.io/rewrite-target: /$2 spec: ingressClassName: nginx rules: - host: abczzz.com http: paths: - path: /httpbin(/|$)(.*) pathType: Prefix backend: service: name: httpbin-service port: number: 8999 Thank you for your time and interest, MikeDemystifying iControl REST Part 6: Token-Based Authentication
iControl REST. It’s iControl SOAP’s baby, brother, introduced back in TMOS version 11.4 as an early access feature but released fully in version 11.5. Several articles on basic usage have been written on iControl REST so the intent here isn’t basic use, but rather to demystify some of the finer details of using the API. This article will cover the details on how to retrieve and use an authentication token from the BIG-IP using iControl REST and the python programming language. This token is used in place of basic authentication on API calls, which is a requirement for external authentication. Note that for configuration changes, version 12.0 or higher is required as earlier versions will trigger an un-authorized error. The tacacs config in this article is dependent on a version that I am no longer able to get installed on a modern linux flavor. Instead, try this Dockerized tacacs+ server for your testing. The Fine Print The details of the token provider are here in the wiki. We’ll focus on a provider not listed there: tmos. This provider instructs the API interface to use the provider that is configured in tmos. For this article, I’ve configured a tacacs server and the BIG-IP with custom remote roles as shown below to show BIG-IP version 12’s iControl REST support for remote authentication and authorization. Details for how this configuration works can be found in the tacacs+ article I wrote a while back. BIG-IP tacacs+ configuration auth remote-role { role-info { adm { attribute F5-LTM-User-Info-1=adm console %F5-LTM-User-Console line-order 1 role %F5-LTM-User-Role user-partition %F5-LTM-User-Partition } mgr { attribute F5-LTM-User-Info-1=mgr console %F5-LTM-User-Console line-order 2 role %F5-LTM-User-Role user-partition %F5-LTM-User-Partition } } } auth remote-user { } auth source { type tacacs } auth tacacs system-auth { debug enabled protocol ip secret $M$Zq$T2SNeIqxi29CAfShLLqw8Q== servers { 172.16.44.20 } service ppp } Tacacs+ Server configuration id = tac_plus { debug = PACKET AUTHEN AUTHOR access log = /var/log/access.log accounting log = /var/log/acct.log host = world { address = ::/0 prompt = "\nAuthorized Access Only!\nTACACS+ Login\n" key = devcentral } group = adm { service = ppp { protocol = ip { set F5-LTM-User-Info-1 = adm set F5-LTM-User-Console = 1 set F5-LTM-User-Role = 0 set F5-LTM-User-Partition = all } } } group = mgr { service = ppp { protocol = ip { set F5-LTM-User-Info-1 = mgr set F5-LTM-User-Console = 1 set F5-LTM-User-Role = 100 set F5-LTM-User-Partition = all } } } user = user_admin { password = clear letmein00 member = adm } user = user_mgr { password = clear letmein00 member = mgr } } Basic Requirements Before we look at code, however, let’s take a look at the json payload requirements, followed by response data from a query using Chrome’s Advanced REST Client plugin. First, since we are sending json payload, we need to add the Content-Type: application/json header to the query. The payload we are sending with the post looks like this: { "username": "remote_auth_user", "password": "remote_auth_password", "loginProviderName": "tmos" } You submit the same remote authentication credentials in the initial basic authentication as well, no need to have access to the default admin account credentials. A successful query for a token returns data like this: { username: "user_admin" loginReference: { link: "https://localhost/mgmt/cm/system/authn/providers/tmos/1f44a60e-11a7-3c51-a49f-82983026b41b/login" }- token: { uuid: "4d1bd79f-dca7-406b-8627-3ad262628f31" name: "5C0F982A0BF37CBE5DE2CB8313102A494A4759E5704371B77D7E35ADBE4AAC33184EB3C5117D94FAFA054B7DB7F02539F6550F8D4FA25C4BFF1145287E93F70D" token: "5C0F982A0BF37CBE5DE2CB8313102A494A4759E5704371B77D7E35ADBE4AAC33184EB3C5117D94FAFA054B7DB7F02539F6550F8D4FA25C4BFF1145287E93F70D" userName: "user_admin" user: { link: "https://localhost/mgmt/cm/system/authn/providers/tmos/1f44a60e-11a7-3c51-a49f-82983026b41b/users/34ba3932-bfa3-4738-9d55-c81a1c783619" }- groupReferences: [1] 0: { link: "https://localhost/mgmt/cm/system/authn/providers/tmos/1f44a60e-11a7-3c51-a49f-82983026b41b/user-groups/21232f29-7a57-35a7-8389-4a0e4a801fc3" }- - timeout: 1200 startTime: "2015-11-17T19:38:50.415-0800" address: "172.16.44.1" partition: "[All]" generation: 1 lastUpdateMicros: 1447817930414518 expirationMicros: 1447819130415000 kind: "shared:authz:tokens:authtokenitemstate" selfLink: "https://localhost/mgmt/shared/authz/tokens/4d1bd79f-dca7-406b-8627-3ad262628f31" }- generation: 0 lastUpdateMicros: 0 } Among many other fields, you can see the token field with a very long hexadecimal token. That’s what we need to authenticate future API calls. Requesting the token programmatically In order to request the token, you first have to supply basic auth credentials like normal. This is currently required to access the /mgmt/shared/authn/login API location. The basic workflow is as follows (with line numbers from the code below in parentheses): Make a POST request to BIG-IP with basic authentication header and json payload with username, password, and the login provider (9-16, 41-47) Remove the basic authentication (49) Add the token from the post response to the X-F5-Auth-Token header (50) Continue further requests like normal. In this example, we’ll create a pool to verify read/write privileges. (1-6, 52-53) And here’s the code (in python) to make that happen: def create_pool(bigip, url, pool): payload = {} payload['name'] = pool pool_config = bigip.post(url, json.dumps(payload)).json() return pool_config def get_token(bigip, url, creds): payload = {} payload['username'] = creds[0] payload['password'] = creds[1] payload['loginProviderName'] = 'tmos' token = bigip.post(url, json.dumps(payload)).json()['token']['token'] return token if __name__ == "__main__": import os, requests, json, argparse, getpass requests.packages.urllib3.disable_warnings() parser = argparse.ArgumentParser(description='Remote Authentication Test - Create Pool') parser.add_argument("host", help='BIG-IP IP or Hostname', ) parser.add_argument("username", help='BIG-IP Username') parser.add_argument("poolname", help='Key/Cert file names (include the path.)') args = vars(parser.parse_args()) hostname = args['host'] username = args['username'] poolname = args['poolname'] print "%s, enter your password: " % args['username'], password = getpass.getpass() url_base = 'https://%s/mgmt' % hostname url_auth = '%s/shared/authn/login' % url_base url_pool = '%s/tm/ltm/pool' % url_base b = requests.session() b.headers.update({'Content-Type':'application/json'}) b.auth = (username, password) b.verify = False token = get_token(b, url_auth, (username, password)) print '\nToken: %s\n' % token b.auth = None b.headers.update({'X-F5-Auth-Token': token}) response = create_pool(b, url_pool, poolname) print '\nNew Pool: %s\n' % response Running this script from the command line, we get the following response: FLD-ML-RAHM:scripts rahm$ python remoteauth.py 172.16.44.15 user_admin myNewestPool1 Password: user_admin, enter your password: Token: 2C61FE257C7A8B6E49C74864240E8C3D3592FDE9DA3007618CE11915F1183BF9FBAF00D09F61DE15FCE9CAB2DC2ACC165CBA3721362014807A9BF4DEA90BB09F New Pool: {u'generation': 453, u'minActiveMembers': 0, u'ipTosToServer': u'pass-through', u'loadBalancingMode': u'round-robin', u'allowNat': u'yes', u'queueDepthLimit': 0, u'membersReference': {u'isSubcollection': True, u'link': u'https://localhost/mgmt/tm/ltm/pool/~Common~myNewestPool1/members?ver=12.0.0'}, u'minUpMembers': 0, u'slowRampTime': 10, u'minUpMembersAction': u'failover', u'minUpMembersChecking': u'disabled', u'queueTimeLimit': 0, u'linkQosToServer': u'pass-through', u'queueOnConnectionLimit': u'disabled', u'fullPath': u'myNewestPool1', u'kind': u'tm:ltm:pool:poolstate', u'name': u'myNewestPool1', u'allowSnat': u'yes', u'ipTosToClient': u'pass-through', u'reselectTries': 0, u'selfLink': u'https://localhost/mgmt/tm/ltm/pool/myNewestPool1?ver=12.0.0', u'serviceDownAction': u'none', u'ignorePersistedWeight': u'disabled', u'linkQosToClient': u'pass-through'} You can test this out in the Chrome Advanced Rest Client plugin, or from the command line with curl or any other language supporting REST clients as well, I just use python for the examples well, because I like it. I hope you all are digging into iControl REST! What questions do you have? What else would you like clarity on? Drop a comment below.
