using '--resolve' in the pool monitor health check
Hello, I am checking if it's possible to add the option '--resolve' in the health check monitor and avoid using a custom monitor (which consumes too much memory). For example: curl -kvs https://some_site_in_the_internet.com/ready --resolve some_site_in_the_internet.com:443:196.196.12.12 I know you can use curl -kvs https://196.196.12.12/ready --header "host: some_site_in_the_internet.com" But the path to the servers has some TLS requirements that' does not work. Any ideas are welcome Thanks
Big-IP sending Health Check to not-used Node-IP
Hello everyone, my customer recently noticed while checking traffic on his firewall that healt checks are send from the Big-IPs internal self-ip to an IP that fits into the address range of the nodes in use on the f5. This node ip is not known to the customer, and by searching the node table or looking in /var/log/ltm we were unable to find this ip-address. So either this node was used a while ago and the node object was deleted or the Big-IP send tries talking to this ip via 443 for some other reason. Pings & curls send from the Big-IP fail. Has anyone noticed something like this before? Or is there another way to see where health checks are sent? Thanks and regardsStandby Has Fewer Online VIPs Than Active – Requires Manual Monitor Reset
Hello F5 community, I’ll preface this by saying that networking has been verified as fully routable between the Active and Standby units. Both devices can ping and SSH to each other’s Self-IPs, and rebooting the Standby did not resolve the issue. Issue: Discrepancy in Online VIPs Between Active & Standby Despite being In-Sync, the Active and Standby units show a different number of Online VIPs. If I randomly select one or two VIPs that should be online, remove their monitors, and then re-add them—BOOM, the VIP comes online. The VIPs in question were both HTTPS (443). Side Note: Frequent TCP Monitor Failures In my environment, I also frequently see generic ‘TCP’ monitors failing, leading to outages. While I understand that TCP monitoring alone isn’t ideal, my hands are tied as all changes must go through upper management for approval. Has anyone encountered a similar issue where VIPs don’t come online until the monitor is manually reset? Any insights into potential root causes or troubleshooting steps would be greatly appreciated! Thanks in advance.BIG-IP DNS: Check Status Of Multiple Monitors Against Pool Member
Good day, everyone! Within the LTM platform, if a Pool is configured with "Min 1 of" with multiple monitors, you can check the status per monitor via tmsh show ltm monitor <name>, or you can click the Pool member in the TMUI and it will show you the status of each monitor for that member. I cannot seem to locate a similar function on the GTM/BIG-IP DNS platform. We'd typically use this methodology when transitioning to a new type of monitor, where we can passively test connectivity without the potential for impact prior to removing the previous monitor. Does anyone have a way through tmsh or the TMUI where you can check an individual pool member's status against the multiple monitors configured for its pool? Thanks, all!snmp-check external monitor
Problem this snippet solves: This external monitor script runs an snmpget to pool members and marks the members up or down based upon the result. Specifically created for this GTM/APM use case, but can be modified as needed. How to use this snippet: copy the contents of this file into /config/monitors/snmp-check, and then in the external monitor configuration, reference the monitor and provide the following variable key/value pairs: result=<result> community=<community> OID=<oid> Code : #!/bin/sh # # (c) Copyright 1996-2005 F5 Networks, Inc. # # This software is confidential and may contain trade secrets that are the # property of F5 Networks, Inc. No part of the software may be disclosed # to other parties without the express written consent of F5 Networks, Inc. # It is against the law to copy the software. No part of the software may # be reproduced, transmitted, or distributed in any form or by any means, # electronic or mechanical, including photocopying, recording, or information # storage and retrieval systems, for any purpose without the express written # permission of F5 Networks, Inc. Our services are only available for legal # users of the program, for instance in the event that we extend our services # by offering the updating of files via the Internet. # # @(#) $Id: sample_monitor,v 1.3 2005/02/04 18:47:17 saxon Exp $ # # # these arguments supplied automatically for all external pingers: # $1 = IP (nnn.nnn.nnn.nnn notation or hostname) # $2 = port (decimal, host byte order) # $3 and higher = additional arguments # # $MONITOR_NAME = name of the monitor # # In this sample script, $3 is the regular expression # #These lines are required to control the process ID of the monitor pidfile="/var/run/$MONITOR_NAME.$1..$2.pid" if [ -f $pidfile ] then kill -9 `cat $pidfile` > /dev/null 2>&1 fi echo "$$" > $pidfile #Since version9 uses the ipv6 native version of the IP address, parse that down #for usage node_ip=`echo $1 | sed 's/::ffff://'` #Log the variables for debugging #echo IP= $node_ip Port =$2 OID= $OID comm= $community result= $result >> /var/tmp/test #Create a variable called answer that contains the result of the snmpwalk. answer=`snmpget $node_ip -c $community -O v $OID | awk '{print $2}'` #Log the answer for debugging #echo Answer= $answer >> /var/tmp/test if [ $answer -lt $result ] then echo "up" fi rm -f $pidfile Tested this on version: No Version Found
VIPRION external monitor
Problem this snippet solves: This VIPRION specific external monitor script is written in bash and utilizes TMSH to extend the built-in monitoring functionality of BIG-IP version 10.2.3. This write-up assumes the reader has working knowledge writing BIG-IP LTM external monitors. The following link is a great starting point LTM External Monitors: The Basics | DevCentral Logical network diagram: NOTE: The monitor is written to meet very specific environmental requirements. Therefore, your implementation may vary greatly. This post is inteded to show you some requirements for writing external monitors on the VIPRION platform while offering some creative ways to extend the functionality of external monitors using TMSH. The VIPRION acts as a hop in the default path of traffic destined for the Internet. Specific application flows are vectored to optimization servers and all other traffic is passed to the next hop router (Router C) toward the Internet. Router A and Router C are BGP neighbors through the VIPRION. Router B is a BGP neighbor with the VIPRION via ZebOS. A virtual address has route health injection enabled. The script monitors a user defined (agrument to the script) pool and transitions into the failed state when the available pool member count drops below a threshold value (argument to the script). In the failed state the following actions are performed once, effectively stopping client traffic flow through the VIPRION. Two virtual servers (arguments to the script) are disable to stop traffic through VIPRION. A virtual address (argument to the script) is disabled to disable route health injection of the address. All non Self-IP BGP connections are found in the connection table and deleted. NOTE: Manual intervention is required to enable virtual servers and virtual address when the monitor transitions from failed state to successful state before normal traffic flows will proceed. How to use this snippet: The monitor definition: monitor eavbgpv3 { defaults from external interval 20 timeout 61 args "poolhttp 32 vsforward1 vsforward2 10.10.10.1"v DEBUG "0"v run "rhi_v3.bsh" } This external monitor is configured to check for available members in the pool "poolhttp". When the available members falls below 32 the monitor transistions into the failed state and disables the virtual servers "vsforward1" and "vs_forward2" and disables the virtual address "10.10.10.1". When the available pool members increases above 32 neither the virtuals servers nor the virtual address is enabled. This will require manual intervention. The external monitor is assigned to a phantom pool with a single member "1.1.1.1:4353". No traffic is sent to the pool member. This pool and pool member are in place so the operator can see the current status of the external monitor. The Pool definition: pool bgpmonitor { monitor all eavbgp_v3 members 1.1.1.1:f5-iquery {} } You can download the script here: rhi_v3.bsh CODE: #!/bin/bash # (c) Copyright 1996-2007 F5 Networks, Inc. # # This software is confidential and may contain trade secrets that are the # property of F5 Networks, Inc. No part of the software may be disclosed # to other parties without the express written consent of F5 Networks, Inc. # It is against the law to copy the software. No part of the software may # be reproduced, transmitted, or distributed in any form or by any means, # electronic or mechanical, including photocopying, recording, or information # storage and retrieval systems, for any purpose without the express written # permission of F5 Networks, Inc. Our services are only available for legal # users of the program, for instance in the event that we extend our services # by offering the updating of files via the Internet. # # author: Paul DeHerrera pauld@f5.com # # these arguments supplied automatically for all external monitors: # $1 = IP (nnn.nnn.nnn.nnn notation or hostname) # $2 = port (decimal, host byte order) -- not used in this monitor, assumes default port 53 # # these arguments must be supplied in the monitor configuration: # $3 = name of pool to monitor # $4 = threshold value of the pool. If the available pool member count drops below this value the monitor will respond in 'failed' state # $5 = first Virtual server to disable # $6 = second Virtual server to disable # $7 = first Virtual address to disable # $8 = second Virtual address to disable ### Check for the 'DEBUG' variable, set it here if not present. # is the DEBUG variable passed as a variable? if [ -z "$DEBUG" ] then # If the monitor config didn't specify debug as a variable then enable/disable it here DEBUG=0 fi ### If Debug is on, output the script start time to /var/log/ltm # capture and log (when debug is on) a timestamp when this eav starts export ST=`date +%Y%m%d-%H:%M:%S` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): started at $ST" | logger -p local0.debug; fi ### Do not execute this script within the first 300 seconds after BIG-IP boot. This is a customer specific requirement # this section is used to introduce a delay of 300 seconds after system boot before executing this eav for the first time BOOT_DATE=`who -b | grep -i 'system boot' | awk {'print $3 " " $4 " " $5'}` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): boot_date: ($BOOT_DATE)" | logger -p local0.debug; fi EPOCH_DATE=`date -d "$BOOT_DATE" +%s` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): epoch_date: ($EPOCH_DATE)" | logger -p local0.debug; fi EPOCH_DATE=$((${EPOCH_DATE}+300)) if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): epoch_date +300: ($EPOCH_DATE)" | logger -p local0.debug; fi CUR_DATE=`date +%s` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): current_date: ($CUR_DATE)" | logger -p local0.debug; fi if [ $CUR_DATE -ge $EPOCH_DATE ] then ### Assign a value to variables. The VIPRION requires some commands to be executed on the Primary slot as you will see later in this script # export some variables if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): exporting variables..." | logger -p local0.debug; fi export REMOTEUSER="root" export HOME="/root" export IP=`echo $1 | sed 's/::ffff://'` export PORT=$2 export POOL=$3 export MEMBER_THRESHOLD=$4 export VIRTUAL_SERVER1=$5 export VIRTUAL_SERVER2=$6 export VIRTUAL_ADDRESS1=$7 export VIRTUAL_ADDRESS2=$8 export PIDFILE="/var/run/`basename $0`.$IP.$PORT.pid" export TRACKING_FILENAME=/var/tmp/rhi_bsh_monitor_status export PRIMARY_SLOT=`tmsh list sys db cluster.primary.slot | grep -i 'value' | sed -e 's/\"//g' | awk {'print $NF'}` ### Output the Primary slot to /var/log/ltm if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): the primary blade is in slot number: ($PRIMARY_SLOT)..." | logger -p local0.debug; fi ### This section is for debugging only. Check to see if this script is executing on the Primary blade and output to /var/log/ltm if [ $DEBUG -eq 1 ]; then export PRIMARY_BLADE=`tmsh list sys db cluster.primary | grep -i "value" | sed -e 's/\"//g' | awk {'print $NF'}`; fi if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): is this monitor executing on the primary blade: ($PRIMARY_BLADE)" | logger -p local0.debug; fi ### Standard EAV check to see if an instance of this script is already running for the memeber. If so, kill the previous instance and output to /var/log/ltm # is there already an instance of this EAV running for this member? if [ -f $PIDFILE ] then if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): pid file is present, killing process..." | logger -p local0.debug; fi kill -9 `cat $PIDFILE` > /dev/null 2>&1 echo "EAV `basename $0` ($$): exceeded monitor interval, needed to kill ${IP}:${PORT} with PID `cat $PIDFILE`" | logger -p local0.error fi ### Create a new pid file to track this instance of the monitor for the current member # create a pidfile if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): creating new pid file..." | logger -p local0.debug; fi echo "$$" > $PIDFILE ### Export variables for available pool members and total pool members # export more variables (these require tmsh) export AVAILABLE=`tmsh show /ltm pool $POOL members all-properties | grep -i "Availability" | awk {'print $NF'} | grep -ic "available"` export TOTAL_POOL_MEMBERS=`tmsh show /ltm pool $POOL members all-properties | grep -c "Pool Member"` let "AVAILABLE-=1" ### If Debug is on, output some variables to /var/log/ltm - helps with troubleshooting if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): Pool ($POOL) has ($AVAILABLE) available of ($TOTAL_POOL_MEMBERS) total members." | logger -p local0.debug; fi if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): Pool ($POOL) threshold = ($MEMBER_THRESHOLD) members. Virtual server1 ($VIRTUAL_SERVER1) and Virtual server2 ($VIRTUAL_SERVER2)" | logger -p local0.debug; fi if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): Member Threshold ($MEMBER_THRESHOLD)" | logger -p local0.debug; fi ### If the available members is less than the threshold then we are in a 'failed' state. # main monitor logic if [ "$AVAILABLE" -lt "$MEMBER_THRESHOLD" ] then ### If Debug is on, output status to /var/log/ltm ### notify log - below threshold and disabling virtual server1 if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): AVAILABLE < MEMBER_THRESHOLD, disabling the virtual server..." | logger -p local0.debug; fi if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disabling Virtual Server 1 ($VIRTUAL_SERVER1)" | logger -p local0.debug; fi ### Disable the first virtual server, which may exist in an administrative partition. For version 10.2.3 (possibly others) the script is required to change the 'update-partition' before disabling the virtual server. To accomplish this we first determine the administrative partition name where the virtual is configured then we build a list construct to execute both commands consecutively. ### disable virtual server 1 ### obtain the administrative partition for the virtual. if no administrative partition is found, assume common export VS1_PART=`tmsh list ltm virtual $VIRTUAL_SERVER1 | grep 'partition' | awk {'print $NF'}` if [ -z ${VS1_PART} ]; then ### no administrative partition was found so execute a list construct to change the update-partition to Common and disable the virtual server consecutively export DISABLE1=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition Common && tmsh modify /ltm virtual $VIRTUAL_SERVER1 disabled"` ### If Debug is on, output the command to /var/log/ltm if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disable cmd1: ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT 'tmsh modify cli admin-partitions update-partition Common && tmsh modify /ltm virtual $VIRTUAL_SERVER1 disabled'" | logger -p local0.debug; fi else ### the administrative partition was found so execute a list construct to change the update-partition and disable the virtual server consecutively. The command is sent to the primary slot via SSH export DISABLE1=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition $VS1_PART && tmsh modify /ltm virtual $VIRTUAL_SERVER1 disabled"` ### If Debug is on, output the command to /var/log/ltm if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disable cmd1: ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT 'tmsh modify cli admin-partitions update-partition $VS1_PART && tmsh modify /ltm virtual $VIRTUAL_SERVER1 disabled'" | logger -p local0.debug; fi fi ### If Debug is on, output status to /var/log/ltm if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disabling Virtual Server 2 ($VIRTUAL_SERVER2)" | logger -p local0.debug; fi ### Disable the second virtual server. This section is the same as above, so I will skip the detailed comments here. ### disable virtual server 2 export VS2_PART=`tmsh list ltm virtual $VIRTUAL_SERVER2 | grep 'partition' | awk {'print $NF'}` if [ -z ${VS2_PART} ]; then export DISABLE2=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition Common && tmsh modify /ltm virtual $VIRTUAL_SERVER2 disabled"` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disable cmd2: ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT 'tmsh modify cli admin-partitions update-partition Common && tmsh modify /ltm virtual $VIRTUAL_SERVER2 disabled'" | logger -p local0.debug; fi else export DISABLE2=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition $VS2_PART && tmsh modify /ltm virtual $VIRTUAL_SERVER2 disabled"` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disable cmd2: ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT 'tmsh modify cli admin-partitions update-partition $VS2_PART && tmsh modify ltm virtual $VIRTUAL_SERVER2 disabled'" | logger -p local0.debug; fi fi ### notify log - disconnecting all BGP connection if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): Pool ($POOL) disconnecting all BGP connections..." | logger -p local0.debug; fi ### acquire a list of self IPs SELF_IPS=(`tmsh list net self | grep 'net self' | sed -e 's/\//\ /g' | awk {'print $3'}`) ### start to build our TMSH command excluding self IPs BGP_CONNS="tmsh show sys conn cs-server-port 179 | sed -e 's/\:/\ /g' | egrep -v '" COUNT=1 if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 1 - ${BGP_CONNS}" | logger -p local0.debug; fi ### loop through the self IPs for ip in "${SELF_IPS[@]}" do if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 2 - ${ip}" | logger -p local0.debug; fi ### continue to build our TMSH command - append self IPs to ignore if [ ${COUNT} -gt 1 ] then BGP_CONNS=${BGP_CONNS}"|${ip}" else BGP_CONNS=${BGP_CONNS}"${ip}" fi (( COUNT++ )) done ### if debug is on log a message with the TMSH command up until this point if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 3 - ${BGP_CONNS}" | logger -p local0.debug; fi ### finish the TMSH command to show BGP connections not including self IPs BGP_CONNS=${BGP_CONNS}"' | egrep -v 'Sys|Total' | awk {'print \$1'}" if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 4 - ${BGP_CONNS}" | logger -p local0.debug; fi ### gather all BGP connection not including those to self IPs DISCONNS=(`eval $BGP_CONNS`) DISCMD='' NEWCOUNT=1 if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 5 - ${DISCONNS}" | logger -p local0.debug; fi ### loop through the resulting BGP connections and build another TMSH command to delete these connections from the connection table for newip in "${DISCONNS[@]}" do if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 6" | logger -p local0.debug; fi if [ ${NEWCOUNT} -gt 1 ] then DISCMD=${DISCMD}" && tmsh delete sys connection cs-client-addr ${newip} cs-server-port 179" else DISCMD=${DISCMD}"tmsh delete sys connection cs-client-addr ${newip} cs-server-port 179" fi (( NEWCOUNT++ )) done ### if debug is on log the command we just assembled if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 7 - ${DISCMD}" | logger -p local0.debug; fi ### One the primary slot execute the command to delete the non self IP BGP connections. export CONNECTIONS=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "${DISCMD}"` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): BGP Step 8 - $CONNECTIONS" | logger -p local0.debug; fi ### disable virtual address 1 if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): VA1 ($VIRTUAL_ADDRESS1)" | logger -p local0.debug; fi if [ ! -z "$VIRTUAL_ADDRESS1" ]; then if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disabling Virtual Address 1 ($VIRTUAL_ADDRESS1)" | logger -p local0.debug; fi export VA1_PART=`tmsh list ltm virtual-address $VIRTUAL_ADDRESS1 | grep 'partition' | awk {'print $NF'}` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): cmd: ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT tmsh modify cli admin-partitions update-partition $VA1_PART && tmsh modify /ltm virtual-address $VIRTUAL_ADDRESS1 enabled no " | logger -p local0.debug; fi export VA2_UPCMD=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition $VA1_PART && tmsh modify /ltm virtual-address $VIRTUAL_ADDRESS1 enabled no"` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): virtual address 1 disabled?" | logger -p local0.debug; fi fi ### disable virtual address 2 if [ ! -z "$VIRTUAL_ADDRESS2" ]; then if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): disabling Virtual Address 2 ($VIRTUAL_ADDRESS2)" | logger -p local0.debug; fi export VA2_PART=`tmsh list ltm virtual-address $VIRTUAL_ADDRESS2 | grep 'partition' | awk {'print $NF'}` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): update-partition - $VA2_PART" | logger -p local0.debug; fi export VA2_UPCMD=`ssh -o StrictHostKeyChecking=no root\@slot$PRIMARY_SLOT "tmsh modify cli admin-partitions update-partition $VA2_PART && tmsh modify /ltm virtual-address $VIRTUAL_ADDRESS2 enabled no"` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): cmd: virtual address 2 disabled?" | logger -p local0.debug; fi fi ### track number of times this monitor has failed if [ -e "$TRACKING_FILENAME" ] then export COUNT=`cat $TRACKING_FILENAME` export NEW_COUNT=$((${COUNT}+1)) echo $NEW_COUNT > $TRACKING_FILENAME else echo 1 > $TRACKING_FILENAME export NEW_COUNT=1 fi ### notify log - failure count echo "EAV `basename $0` ($$): Pool $POOL only has $AVAILABLE available of $TOTAL_POOL_MEMBERS total members, failing site. Virtual servers ($VIRTUAL_SERVER1 and $VIRTUAL_SERVER2) will be disabled and all connections with destination port 179 will be terminated. Virtual servers must be manually enabled after pool $MEMBER_THRESHOLD or more pool members are available. This monitor has failed $NEW_COUNT times." | logger -p local0.debug # remove the pidfile if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): removing the pidfile..." | logger -p local0.debug; fi export PIDBGONE=`rm -f $PIDFILE` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): pidfile has been removed ($PIDBGONE)" | logger -p local0.debug; fi export END=`date +%Y%m%d-%H:%M:%S` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): stopped at $END" | logger -p local0.debug; fi else if [ -e "$TRACKING_FILENAME" ] then ### log the status echo "EAV `basename $0` ($$): Pool $POOL has $AVAILABLE members of $TOTAL_POOL_MEMBERS total members. No change to virtual servers ($VIRTUAL_SERVER1 and $VIRTUAL_SERVER2). No change to port 179 connections. Virtual servers must be manually enabled to pass traffic if they are disabled." | logger -p local0.debug rm -f $TRACKING_FILENAME fi ### remove the pidfile if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): removing the pidfile..." | logger -p local0.debug; fi export PIDBGONE=`rm -f $PIDFILE` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): pidfile has been removed ($PIDBGONE)" | logger -p local0.debug; fi export END=`date +%Y%m%d-%H:%M:%S` if [ $DEBUG -eq 1 ]; then echo "EAV `basename $0` ($$): stopped at $END" | logger -p local0.debug; fi echo "UP" fi fiTACACS+ External Monitor (Python)
Problem this snippet solves: This script is an external monitor for TACACS+ that simulates a TACACS+ client authenticating a test user, and marks the status of a pool member as up if the authentication is successful. If the connection is down/times out, or the authentication fails due to invalid account settings, the script marks the pool member status as down. This is heavily inspired by the Radius External Monitor (Python) by AlanTen. How to use this snippet: Prerequisite This script uses the TACACS+ Python client by Ansible (tested on version 2.6). Create the directory /config/eav/tacacs_plus on BIG-IP Copy all contents from tacacs_plus package into /config/eav/tacacs_plus. You may also need to download six.py from https://raw.githubusercontent.com/benjaminp/six/master/six.py and place it in /config/eav/tacacs_plus. You will need to have a test account provisioned on the TACACS+ server for the script to perform authentication. Installation On BIG-IP, import the code snippet below as an External Monitor Program File. Monitor Configuration Set up an External monitor with the imported file, and configure it with the following environment variables: KEY: TACACS+ server secret USER: Username for test account PASSWORD: Password for test account MOD_PATH: Path to location of Python package tacacs_plus, default: /config/eav TIMEOUT: Duration to wait for connectivity to TACACS server to be established, default: 3 Troubleshooting SSH to BIG-IP and run the script locally $ cd /config/filestore/files_d/Common_d/external_monitor_d/ # Get name of uploaded file, e.g.: $ ls -la ... -rwxr-xr-x. 1 tomcat tomcat 1883 2021-09-17 04:05 :Common:tacacs-monitor_39568_7 # Run the script with the corresponding variables $ KEY=<my_tacacs_key> USER=<testuser> PASSWORD=<supersecure> python <external program file, e.g.:Common:tacacs-monitor_39568_7> <TACACS+ server IP> <TACACS+ server port> Code : #!/usr/bin/env python # # Filename : tacacs_plus_mon.py # Author : Leon Seng # Version : 1.2 # Date : 2021/09/21 # Python ver: 2.6+ # F5 version: 12.1+ # # ========== Installation # Import this script via GUI: # System > File Management > External Monitor Program File List > Import... # Name it however you want. # Get, modify and copy the following modules: # ========== Required modules # -- six -- # https://pypi.org/project/six/ # Copy six.py into /config/eav # # -- tacacs_plus -- # https://pypi.org/project/tacacs_plus/ | https://github.com/ansible/tacacs_plus # Copy tacacs_plus directory into /config/eav # ========== Environment Variables # NODE_IP - Supplied by F5 monitor as first argument # NODE_PORT - Supplied by F5 monitor as second argument # KEY - TACACS+ server secret # USER - Username for test account # PASSWORD - Password for test account # MOD_PATH - Path to location of Python package tacacs_plus, default: /config/eav # TIMEOUT - Duration to wait for connectivity to TACACS server to be established, default: 3 import os import socket import sys if os.environ.get('MOD_PATH'): sys.path.append(os.environ.get('MOD_PATH')) else: sys.path.append('/config/eav') # https://github.com/ansible/tacacs_plus from tacacs_plus.client import TACACSClient node_ip = sys.argv[1] node_port = int(sys.argv[2]) key = os.environ.get("KEY") user = os.environ.get("USER") password = os.environ.get("PASSWORD") timeout = int(os.environ.get("TIMEOUT", 3)) # Determine if node IP is IPv4 or IPv6 family = None try: socket.inet_pton(socket.AF_INET, node_ip) family = socket.AF_INET except socket.error: # not a valid address try: socket.inet_pton(socket.AF_INET6, node_ip) family = socket.AF_INET6 except socket.error: sys.exit(1) # Authenticate against TACACS server client = TACACSClient(node_ip, node_port, key, timeout=timeout, family=family) try: auth = client.authenticate(user, password) if auth.valid: print "up" except socket.error: # EAV script marks node as DOWN when no output is present pass Tested this on version: 12.1
