GTM return LDNS IP to client
Problem this snippet solves: We do a lot of our load balancing based on topology rules, so it's often very useful to know where the DNS request is actually coming from rather than just the client's IP and the DNS servers they have configured. Especially if they're behind an ADSL router doing NAT or some other similar set up. This rule simply returns the IP address of the LDNS that eventually made the query to the GTM device in the response to a lookup for the WideIP using the rule, as well as logging the response and perceived location. Code : rule "DNS_debug" partition "Common" { when DNS_REQUEST { host [IP::client_addr] log local0.err "Debug address : [IP::client_addr] [whereis [IP::client_addr]]" } }
Create DNS monitor without external dig or nslookup
Problem this snippet solves: NOTE: This was written in 10.x and early 11.x days. Since then, a native DNS monitor has been added to the product. This example will create a udp monitor with proper send and receive strings to query a DNS server. Much of the heavy lifting was pulled from an iApp template that ships with v11. I have tested this out on as far back as 10.2.1 base. Installation One method to get this into your config would be: In the code block below, click the icon in the top right corner '<>' view source. Ctrl-A, Ctrl-C to select and copy all. Then in tmsh, type 'edit /cli script dns.monitor' If your editor is configured to use vi (the default setting) Type :set paste, then c, then Shift + G. This will clear out the default skeleton. You will now be in insert mode. Press Shift + insert. This will paste in the script. Now save the script by pressing Esc, then typing :wq < enter > and follow the prompts. How to use this snippet: Example root@bigip(Active)(/Common)(tmos)# run cli script dns.monitor xxx Requires 5 arguments: := Name you want to give the monitor := A, NS, PTR, SOA, CNAME := What you are asking the DNS server (send string) := Why you expect for a "healthy" response (recv string) := The frequency you want the monitor to fire e.g. dns.monitor my_dns A www.example.com 192.0.2.55 5 root@bigip(Active)(/Common)(tmos)# run cli script dns.monitor my_dns A www.example.com 192.0.2.55 5 root@bigip(Active)(/Common)(tmos)# list ltm monitor udp my_dns ltm monitor udp my_dns { debug no defaults-from udp destination *:* interval 5 recv \\x00\\x01.*\\x04\\xc0\\x00\\x02\\x37 send \\x96\\x87\\x01\\x00\\x00\\x01\\x00\\x00\\x00\\x00\\x00\\x00\\x03www\\x07example\\x03com\\x00\\x00\\x01\\x00\\x01 time-until-up 0 timeout 16 } root@bigip(Active)(/Common)(tmos)# Code : create script dns.monitor { proc script::init {} { } proc script::run {} { if {$tmsh::argc == 6} { # create monitor set monitor_name [lindex $tmsh::argv 1] set monitor_type [string toupper [ lindex $tmsh::argv 2 ]] switch $monitor_type { A { set monitor_send [generate_monitor_send_string_a_record [lindex $tmsh::argv 3]] set monitor_recv [generate_monitor_recv_string_a_record [lindex $tmsh::argv 4]] } NS { set monitor_send [generate_monitor_send_string_ns_record [lindex $tmsh::argv 3]] set monitor_recv [generate_monitor_recv_string_ns_record [lindex $tmsh::argv 4] [lindex $tmsh::argv 3]] } PTR { set monitor_send [generate_monitor_send_string_ptr_record [lindex $tmsh::argv 3]] set monitor_recv [generate_monitor_recv_string_ptr_record [lindex $tmsh::argv 4]] } SOA { set monitor_send [generate_monitor_send_string_soa_record [lindex $tmsh::argv 3]] set monitor_recv [generate_monitor_recv_string_soa_record [lindex $tmsh::argv 4] [lindex $tmsh::argv 3]] } CNAME { set monitor_send [generate_monitor_send_string_cname_record [lindex $tmsh::argv 3]] set monitor_recv [generate_monitor_recv_string_cname_record [lindex $tmsh::argv 4] [lindex $tmsh::argv 3]] } default { usage } } set monitor_interval [lindex $tmsh::argv 5] set monitor_timeout [ expr { [ expr {$monitor_interval * 3} ] + 1 } ] # doctor the send and receive strings so that they go through as intended set monitor_send [doctor_hex_string $monitor_send] set monitor_recv [doctor_hex_string $monitor_recv] tmsh_create "ltm monitor udp $monitor_name defaults-from udp interval $monitor_interval timeout $monitor_timeout send \"$monitor_send\" recv \"$monitor_recv\"" } else { usage } } proc script::help {} { tmsh::add_help "Create a DNS monitor \n\ " } proc script::tabc {} { } proc tmsh_create { arguments } { regsub -all {\[} $arguments "\\\[" arguments regsub -all {\]} $arguments "\\\]" arguments tmsh::create "$arguments" } proc number_to_hex_string { number } { if { $number < 0 } { set number [ expr {0 - $number} ] } set hex_string [format "\\x%02x" $number] return $hex_string } proc hostname_or_ip_address_to_dns_name { hostname } { set fields [split $hostname .] set dns_name "" foreach field $fields { set len [string length $field] set str_len [number_to_hex_string $len] append dns_name $str_len append dns_name $field } append dns_name "\\x00" return $dns_name } proc hostname_or_ip_address_to_reverse_dns_name { hostname } { set complete_hostname [format "arpa.in-addr.%s" $hostname] set fields [split $complete_hostname .] set dns_name "" foreach field $fields { # if [string is integer $field] { set len [string length $field] set str_len [number_to_hex_string $len] set dns_name [format "%s%s%s" $str_len $field $dns_name] # } } append dns_name "\\x00" return $dns_name } proc get_id { } { set value1 [expr { int(256 * rand()) }] set value2 [expr { int(256 * rand()) }] set id [number_to_hex_string $value1] append id [number_to_hex_string $value2] return $id } proc generate_dns_packet_payload { question } { set payload [get_id] append payload "\\x01\\x00" append payload "\\x00\\x01" append payload "\\x00\\x00" append payload "\\x00\\x00" append payload "\\x00\\x00" append payload $question return $payload } proc ip_addr_to_a_resp_addr { address } { set fields [split $address .] set num_fields 0 set field_encoding "" foreach field $fields { if {[string is integer $field]} { set num_fields [expr { $num_fields + 1 }] set part [number_to_hex_string $field] append field_encoding $part } } set dns_name [number_to_hex_string $num_fields] append dns_name $field_encoding return $dns_name } proc generate_send_payload { input_string record_type_code reverse } { if { $reverse == 0 } { set dns_name [hostname_or_ip_address_to_dns_name $input_string] } else { set dns_name [hostname_or_ip_address_to_reverse_dns_name $input_string] } set internet_address_qclass "\\x00\\x01" set question $dns_name append question $record_type_code append question $internet_address_qclass set send [generate_dns_packet_payload $question] return $send } proc generate_monitor_send_string_a_record { input_string } { set send [generate_send_payload $input_string "\\x00\\x01" 0] return $send } proc generate_monitor_send_string_ns_record { input_string } { set send [generate_send_payload $input_string "\\x00\\x02" 0] return $send } proc generate_monitor_send_string_ptr_record { input_string } { set send [generate_send_payload $input_string "\\x00\\x0c" 1] return $send } proc generate_monitor_send_string_soa_record { input_string } { set send [generate_send_payload $input_string "\\x00\\x06" 0] return $send } proc generate_monitor_send_string_cname_record { input_string } { set send [generate_send_payload $input_string "\\x00\\x05" 0] return $send } proc generate_monitor_recv_string_a_record { input_string } { set a_resp_addr [ip_addr_to_a_resp_addr $input_string] set recv [format "\\x00\\x01.*%s" $a_resp_addr] return $recv } proc generate_monitor_recv_string_ns_record { input_string domain_name } { regsub -all {\.} $domain_name \. domain_name set re [format "^(.*)(\.%s)$" $domain_name] set found [regexp $re $input_string matched new_hostname rest] if { $found != 0 } { set recv_temp [hostname_or_ip_address_to_dns_name $new_hostname] set re {^(.*\\)(x00)$} set found [regexp -nocase $re $recv_temp matched recv rest] if { $found != 0 } { set recv [format "\\x00\\x02.*%sxc0" $recv] } else { set recv [format "\\x00\\x02.*%s" $recv_temp] } } else { set recv [hostname_or_ip_address_to_dns_name $input_string] set recv [format "\\x00\\x02.*%s" $recv] } return $recv } proc generate_monitor_recv_string_ptr_record { input_string } { set dns_name [hostname_or_ip_address_to_dns_name $input_string] set recv [format "\\x00\\x0c.*%s" $dns_name] return $recv } proc generate_monitor_recv_string_soa_record { input_string domain_name } { regsub -all {\.} $domain_name \. domain_name set re [format "^(.*)(\.%s)$" $domain_name] set found [regexp -nocase $re $input_string matched new_hostname rest] if { $found != 0 } { set recv_temp [hostname_or_ip_address_to_dns_name $new_hostname] set re {^(.*)(\\x00)$} set found [regexp -nocase $re $recv_temp matched recv rest] if { $found != 0 } { set recv [format "\\x00\\x06.*%s(\\xc0|\\x05)" $recv] } else { set recv [format "\\x00\\x06.*%s" $recv_temp] } } else { set recv [hostname_or_ip_address_to_dns_name $input_string] set recv [format "\\x00\\x06.*%s" $recv] } return $recv } proc generate_monitor_recv_string_cname_record { input_string hostname } { regsub -all {\.} $hostname \. hostname #puts "hostname = $hostname" set re {^([^\.]+)\.(.+)$} #puts "re = $re" set found [regexp -nocase $re $hostname matched first domain_name] #puts "found = $found" if { $found == 0 } { set domain_name $hostname } regsub -all {\.} $domain_name \. domain_name #puts "domain_name = $domain_name" #puts "input_string = $input_string" set re [format "^(.*)(\.%s)$" $domain_name] #puts "re = $re" set found [regexp -nocase $re $input_string matched new_hostname rest] if { $found != 0 } { set recv_temp [hostname_or_ip_address_to_dns_name $new_hostname] set re {^(.*\\)(x00)$} set found [regexp -nocase $re $recv_temp matched recv rest] if { $found != 0 } { set re {^(.*)(\\x00)$} set found [regexp -nocase $re $recv_temp matched recv rest] set recv [format "\\x00\\x05.*%s(\\xc0|\\x05)" $recv] } else { set recv [format "\\x00\\x05.*%s" $recv_temp] } } else { set recv [hostname_or_ip_address_to_dns_name $input_string] set recv [format "\\x00\\x05.*%s" $recv] } return $recv } proc doctor_hex_string { input } { set pieces [split $input \\ ] set output "" set first_time 1 foreach piece $pieces { if { $first_time == 1 } { set first_time 0 } else { append output {\\} } append output $piece } return $output } proc usage { } { puts "Requires 5 arguments: \n\ := Name you want to give the monitor \n\ := A, NS, PTR, SOA, CNAME \n\ := What you are asking the DNS server (send string) \n\ := Why you expect for a \"healthy\" response (recv string) \n\ := The frequency you want the monitor to fire \n\n\ e.g. [lindex $tmsh::argv 0] A www.example.com 192.0.2.55 5" exit } }Generate private key w/ CSR via iControl REST
Problem this snippet solves: Generate a private key w/ CSR How to use this snippet: To create a private key with a CSR via iControl REST: POST URL:https://10.1.1.165/mgmt/tm/sys/crypto/key Use the data below as your payload. For the name field, it must end in .key or you will get a false 404! Code : { "name":"www.testing.com.key", "commonName":"www.testing.com", "keySize":"4096", "keyType":"rsa-private", "options":[{"gen-csr":"www.testing.com"}], "organization":"Let It Snow Corp.", "ou":"Ice Engineering", "city":"Calhoun", "state":"AZ", "admin-email-address":"jerry@letit.snow", "email-address":"beth@letit.snow", "subject-alternative-name":"DNS:www.testing.com", "challenge-password":"myP4ssword" } Tested this on version: 13.0
FQDN nodes in non-default route domains
Problem this snippet solves: Currently there is no support for FQDN nodes in non-default route domains as per Article. With recent increase in cloud deployment, most of the time there is a requirement from F5 to load balance to servers or ELB in the cloud which has FQDN names as those are having dyanamic IP addresses. If you are using route domains in your BIGIP environment then this becomes a challenge. Below iRule script can be used in those scenerios to use F5 to send traffic to FQDN nodes in non-default route domains. How to use this snippet: If FQDN needs to be resolved by your internal DNS, create performance layer 4 VIP (dns_53) load balancing your DNS servers. DNS server can be used directly in the iRule itself, but it would be better to use a VIP to have redundancy. Create iRule and apply to the VIP Code : when CLIENT_ACCEPTED { set host [RESOLV::lookup @dns_53 "server.example.com"] set ip [getfield $host " " 1] node [lindex $ip 0]%<Rd> 443 } Tested this on version: 14.1BIG-IP Report
Problem this snippet solves: Overview This is a script which will generate a report of the BIG-IP 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 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 auditor (read-only) permissions on your devices. Demo/Preview Interactive demo http://loadbalancing.se/bigipreportdemo/ Screen shots The main report: The device overview: Certificate details: How to use this snippet: 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). Downloads (two latest versions): https://loadbalancing.se/downloads/bigipreport-v5.7.11.zip https://loadbalancing.se/downloads/bigipreport-v5.7.10.zip Documentation, installation instructions and troubleshooting:https://loadbalancing.se/bigipreport-rest/ Docker support https://loadbalancing.se/2021/01/05/running-bigipreport-on-docker/ Kubernetes support https://loadbalancing.se/2021/04/16/bigipreport-on-kubernetes/ BIG-IP Report (Legacy) Older version of the report that only runs on Windows and is depending on a Powershell plugin originally written by Joe Pruitt (F5) BIG-IP Report (only download this if you have v10 devices): 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. --- Join us on Discord: https://discord.gg/7JJvPMYahA Code : BigIP Report Tested this on version: 12, 13, 14, 15, 16
BIG-IP Wide-IP to F5XC DNSLB converter
This is a conceptual sample script that converts BIG-IP Wide-IP records to F5XC DNSLB records. This bash script can be run using a cron job to check for configuration changes and synchronize them to F5XC. We used the F5XC API to post and update the configuration. You need to get an APIToken from your F5XC tenant and change the value on the POST commands on the script below. Note: Since this is not a full-blown converter script, it is limited to handling only a single Wide-IP pool member. You need to configure a GTM pool to include the IP addresses that need to be load balanced. Check the main article for more details. #!/bin/bash # Get list of wide IPs wideip_output=$(tmsh list gtm wideip all-properties one-line) # Get list of Pool pool_output=$(tmsh list gtm pool a one-line all-properties) # Declare associative arrays declare -A wideip_list declare -A current_wideip_info declare -A zone_array declare -A subdomain_info declare -A a_record_per_zone declare -A pool_list declare -A membersip_array # Unset variables function unset_arrays { unset current_wideip_info name subdomain domain type aliases description status failure_rcode last_resort_pool load_balancing_decision_log metadata minimal_response partition persist_cidr_ipv4 persist_cidr_ipv6 persistence pool_lb_mode pools pool_cname topology_edns0 ttl_persistence poolnames poolnames_array zone_array subdomain_info a_record_per_zone dnslb_name pool_list membersip_array } # Print wide IP details function print_wideip { for wideip in "${!wideip_list[@]}"; do echo "Wide IP: $wideip, Details: ${wideip_list[$wideip]}" done } # Create Zone function create_zone { curl -X POST -H "Authorization: APIToken XXXXX" -H "Accept: application/json" -H "Access-Control-Allow-Origin: *" -H "x-volterra-apigw-tenant: cag-waap2023" -H "Content-Type: application/json" -d "{\"metadata\":{\"name\":\"$zone\",\"namespace\":\"system\"},\"spec\":{\"primary\":{\"allow_http_lb_managed_records\":true},\"default_soa_parameters\":{},\"dnssec_mode\":{},\"rr_set_group\":[],\"soa_parameters\":{\"refresh\":3600,\"expire\":0,\"retry\":60,\"negative_ttl\":0,\"ttl\":0}}}" https://cag-waap2023.console.ves.volterra.io/api/config/dns/namespaces/system/dns_zones } # Create DNSLB function create_dnslb { curl -X POST -H "Authorization: APIToken XXXXX" -H "Accept: application/json" -H "Access-Control-Allow-Origin: *" -H "x-volterra-apigw-tenant: cag-waap2023" -H "Content-Type: application/json" -d "{\"metadata\":{\"name\":\"$dnslbname\",\"namespace\":\"system\",\"labels\":{},\"annotations\":{},\"disable\":false},\"spec\":{\"record_type\":\"A\",\"rule_list\":{\"rules\":[{\"geo_location_set\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"geo-1\",\"kind\":\"geo_location_set\"},\"pool\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"$xcdnslbpoolname\",\"kind\":\"dns_lb_pool\"},\"score\":100}]},\"response_cache\":{\"disable\":{}}}}" https://cag-waap2023.console.ves.volterra.io/api/config/dns/namespaces/system/dns_load_balancers } # Loop through each line of output while IFS= read -r line; do pool_name=$(awk '{print $4}' <<< "$line") dnslbpool_name=$(echo "$pool_name" | sed 's/[^a-zA-Z0-9]/-/g; s/.*/\L&/') pool_type=$(awk '{print $3}' <<< "$line") lbmode=$(grep -o 'load-balancing-mode [^ ]*' <<< "$line" | awk '{print $2}') # Convert load_balancing_mode to lowercase if it is "ROUND_ROBIN" if [[ "$lbmode" == "round-robin" ]]; then lbmode="ROUND_ROBIN" elif [[ "$lbmode" == "static-persistence" ]]; then lbmode="STATIC_PERSIST" elif [[ "$lbmode" == "global-availability" ]]; then lbmode="PRIORITY" elif [[ "$lbmode" == "ratio" ]]; then lbmode="RATIO_MEMBER" fi # Extract members block using awk #members=$(awk -F 'members {| }' '{print $2}' <<< "$line") members=$(echo "$line" | grep -o -P '(?<=members \{ ).*?(?=\} \})') membernames=$(echo "$members" | grep -oP '\S+(?=\s*{)') # Temporary array to hold member IP addresses declare -a temp_members_array temp_members_array=($(awk -F ':' '{print $2}' <<< "$membernames")) monitor=$(awk -F 'monitor ' '{print $2}' <<< "$line" | awk '{print $1}') ttl=$(awk '{print $2}' <<< "$(grep -o 'ttl [^ ]*' <<< "$line")") # Assign values to the associative array membersip_array["$dnslbpool_name"]="${temp_members_array[@]}" # Store extracted values in the array pool_list["$dnslbpool_name"]="pool_type: $pool_type, lbmode: $lbmode, monitor: $monitor, members: ${membersip_array["$dnslbpool_name"]}, ttl: $ttl" done <<< "$pool_output" # Loop through each pool in the pool_list for dnslbpool_name in "${!pool_list[@]}"; do # Extract only the TTL value from the string ttl=$(awk -F 'ttl: ' '{print $2}' <<< "${pool_list[$dnslbpool_name]}") lbmode=$(awk -F 'lbmode: ' '{print $2}' <<< "${pool_list[$dnslbpool_name]}" | awk -F ',' '{print $1}') members=$(awk -F 'members: ' '{print $2}' <<< "${pool_list[$dnslbpool_name]}" | awk -F ',' '{print $1}') pool_type=$(awk -F 'pool_type: ' '{print $2}' <<< "${pool_list[$dnslbpool_name]}" | awk -F ',' '{print $1}') # Check if pool_type is "a" if [[ "$pool_type" == "a" ]]; then # Initialize an empty string to store the JSON strings members_string="" # Loop through each record in the current zone for ip in ${membersip_array["$dnslbpool_name"]}; do # Create JSON string for each member and append to the existing string members_string+="{\"ip_endpoint\":\"$ip\",\"ratio\":10,\"priority\":1}," done # Remove the trailing comma from the JSON string members_string="${members_string%,}" # Create DNSLB Pools curl -X POST \ -H "Authorization: APIToken Rs0aGJm/lda/JmbE00c9lFXWw4I=" \ -H "Accept: application/json" \ -H "Access-Control-Allow-Origin: *" \ -H "x-volterra-apigw-tenant: cag-waap2023" \ -H "Content-Type: application/json" \ -d "{\"metadata\":{\"name\":\"$dnslbpool_name\",\"namespace\":\"system\"},\"spec\":{\"a_pool\":{\"members\":[$members_string],\"disable_health_check\":null,\"max_answers\":1},\"ttl\":\"$ttl\",\"load_balancing_mode\":\"$lbmode\"}}" \ "https://cag-waap2023.console.ves.volterra.io/api/config/dns/namespaces/system/dns_lb_pools" fi done # Unset variables to free up memory unset pool_list membersip_array # Loop through each line of output while IFS= read -r line; do # Extracting specific details using awk and sed based on the current line name=$(echo "$line" | awk '{print $4}') dnslb_name=$(echo "$name" | sed 's/\./-/g') subdomain=$(echo "$name" | cut -d'.' -f1) domain=$(echo "$name" | sed 's/^[^.]*\.//') type=$(echo "$line" | awk '{print $3}') aliases=$(echo "$line" | grep -o 'aliases [^}]*' | awk '{print $2}') description=$(echo "$line" | grep -o 'description [^ ]*' | sed 's/description //') status=$(echo "$line" | awk '{print $12}') failure_rcode=$(echo "$line" | grep -o 'failure-rcode [^ ]*' | sed 's/failure-rcode //') last_resort_pool=$(echo "$line" | grep -o 'last-resort-pool [^ ]*' | sed 's/last-resort-pool //') load_balancing_decision_log=$(echo "$line" | grep -o 'load-balancing-decision-log-verbosity [^ ]*' | sed 's/load-balancing-decision-log-verbosity //') metadata=$(echo "$line" | grep -o 'metadata [^ ]*' | sed 's/metadata //') minimal_response=$(echo "$line" | grep -o 'minimal-response [^ ]*' | sed 's/minimal-response //') partition=$(echo "$line" | grep -o 'partition [^ ]*' | sed 's/partition //') persist_cidr_ipv4=$(echo "$line" | grep -o 'persist-cidr-ipv4 [^ ]*' | sed 's/persist-cidr-ipv4 //') persist_cidr_ipv6=$(echo "$line" | grep -o 'persist-cidr-ipv6 [^ ]*' | sed 's/persist-cidr-ipv6 //') persistence=$(echo "$line" | grep -o ' persistence [^ ]*' | sed 's/persistence //') pool_lb_mode=$(echo "$line" | grep -o 'pool-lb-mode [^ ]*' | sed 's/pool-lb-mode //') pools=$(echo "$line" | grep -o -P '(?<=pools \{ ).*?(?=\} \})') pool_cname=$(echo "$line" | grep -o 'pools-cname [^ ]*' | sed 's/pools-cname //') topology_edns0=$(echo "$line" | grep -o 'topology-prefer-edns0-client-subnet [^ ]*' | sed 's/topology-prefer-edns0-client-subnet //') ttl_persistence=$(echo "$line" | grep -o 'ttl-persistence [^ ]*' | sed 's/ttl-persistence //') # Use grep to find strings before "{" poolnames=$(echo "$pools" | grep -oP '\S+(?=\s*{)' | sed 's/[^a-zA-Z0-9]/-/g; s/.*/\L&/') # Convert matches to an array readarray -t poolnames_array <<< "$poolnames" # Store extracted values in the associative array current_wideip_info=([Type]="$type" [Subdomain]="$subdomain" [Domain]="$domain" [Status]="$status" [DNSLB]="$dnslb_name" [Pools]="${poolnames_array[@]}" [Pool_LB_Mode]="$pool_lb_mode") # Assign wideip_info to wideip_list wideip_list["$name"]="${current_wideip_info[@]}" # Add subdomains to zone_array if [ -n "${zone_array[$domain]}" ]; then zone_array["$domain"]="${zone_array[$domain]},$subdomain" else zone_array["$domain"]=$subdomain fi # Store subdomain information in subdomain_info array subdomain_info["$subdomain"]="${current_wideip_info[@]}" # Store subdomain type "a" and add it to the array for that zone if [ "$type" == "a" ]; then a_record_per_zone[$domain]="${a_record_per_zone[$domain]}${a_record_per_zone[$domain]:+,}$subdomain" fi done <<< "$wideip_output" for zone in "${!zone_array[@]}"; do create_zone done # Loop through each domain in a_record_per_zone and echo its A record subdomains for domain in "${!a_record_per_zone[@]}"; do echo "Domain: $domain" echo "A Record Subdomains: ${a_record_per_zone[$domain]}" echo "--------------------------" # Initialize an empty string to store the JSON strings a_records_string="" # Loop through each record in the current zone for record in ${a_record_per_zone[$domain]//,/ }; do # Create JSON string for each A record and append to the existing string xcdnslbpoolname=$(echo ${wideip_list[$record.$domain]} | awk '{for (i=6; i<=(NF-1); i++) {printf "%s", $i; if (i < NF-1) printf " "}}') #echo "${a_record_per_zone[$domain]}" #echo "xcdnslbpoolname: $xcdnslbpoolname" # Check if xcdnslbpoolname has multiple strings if [[ $xcdnslbpoolname == *" "* ]]; then echo "Multiple strings found in xcdnslbpoolname" # Split xcdnslbpoolname into an array based on space IFS=' ' read -ra pool_names <<< "$xcdnslbpoolname" # Initialize an empty string to store the JSON strings pools_string="" # Loop through each pool name in the array for pool_name in "${pool_names[@]}"; do # Create JSON string for each member and append to the existing string pools_string+="{\"geo_location_set\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"geo-1\",\"kind\":\"geo_location_set\"},\"pool\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"$pool_name\",\"kind\":\"dns_lb_pool\"},\"score\":100}," done # Remove the trailing comma from the JSON string pools_string="${pools_string%,}" else pools_string="{\"geo_location_set\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"geo-1\",\"kind\":\"geo_location_set\"},\"pool\":{\"tenant\":\"cag-waap2023-gwjvytud\",\"namespace\":\"system\",\"name\":\"$xcdnslbpoolname\",\"kind\":\"dns_lb_pool\"},\"score\":100}" fi dnslbname=$(echo "dnslb-$record-$domain" | sed 's/\./-/g') #create_dnslb curl -X POST -H "Authorization: APIToken XXXXX" -H "Accept: application/json" -H "Access-Control-Allow-Origin: *" -H "x-volterra-apigw-tenant: cag-waap2023" -H "Content-Type: application/json" -d "{\"metadata\":{\"name\":\"$dnslbname\",\"namespace\":\"system\",\"labels\":{},\"annotations\":{},\"disable\":false},\"spec\":{\"record_type\":\"A\",\"rule_list\":{\"rules\":[$pools_string]},\"response_cache\":{\"disable\":{}}}}" https://cag-waap2023.console.ves.volterra.io/api/config/dns/namespaces/system/dns_load_balancers a_records_string+="{\"ttl\":3600,\"lb_record\": {\"name\":\"$record\",\"value\":{\"namespace\": \"system\",\"name\":\"$dnslbname\"}}}," done # Remove the trailing comma from the JSON string a_records_string="${a_records_string%,}" # Print the final JSON string echo "$a_records_string" #update zone record curl -X PUT -H "Authorization: APIToken XXXXX" -H "Accept: application/json" -H "Access-Control-Allow-Origin: *" -H "x-volterra-apigw-tenant: cag-waap2023" -H "Content-Type: application/json" -d "{\"metadata\":{\"name\":\"$domain\",\"namespace\":\"system\"},\"spec\":{\"primary\":{\"allow_http_lb_managed_records\":true,\"default_rr_set_group\":[$a_records_string],\"default_soa_parameters\":{},\"dnssec_mode\":{},\"rr_set_group\":[],\"soa_parameters\":{\"refresh\":3600,\"expire\":0,\"retry\":60,\"negative_ttl\":0,\"ttl\":0}}}}" https://cag-waap2023.console.ves.volterra.io/api/config/dns/namespaces/system/dns_zones/$domain done unset_arraysF5 BIG-IP iRule based TCL DNS server
Short Description This code is for the purpose if there is a need to return a custom DNS reply not from the main DNS server but from the F5 Virtual Server. Problem solved by this Code Snippet The code is meant for small lab or dev environments as F5 has F5 DNS/GTM for replying to DNS requests with Intelligent Load Balancing, DNS Express Memory cache etc. How to use this Code Snippet Modify the irule code to configure the custom domain you want replies from the irule code and not the real DNS server. Add the irule to a DNS UDP LB Code Snippet Meta Information Version: 17.1 Coding Language: TCL Code You can find the code and further documentation in my GitHub repository: irule_dns/irule1 at main · Nikoolayy1/irule_dns (github.com)DNS Query Name Parsing iRule
Problem this snippet solves: This iRule will extract the DNS Query Name in the absence of a DNS profile being applied to a Virtual Server. How to use this snippet: # This is a shameless rip from an old Devcentral post DNS Hostname Parsing iRule that, to the best of my knowledge, never made it to a Code Share. To use this code, simply apply this to a UDP Virtual Server that processes DNS traffic. (No DNS Profile necessary). Code : when FLOW_INIT { #extract QNAME from QUESTION header #${i} is a sanity check so this logic won't spin on invalid QNAMEs set i 0 #initialize our position in the QNAME parsing and the text QNAME set offset 12 set length 1 set endlength 1 set name "" #/extract QNAME from QUESTION header while {${length} > 0 && ${i} < 10} { #length contains the first part length binary scan [string range [DATAGRAM::udp payload] ${offset} ${offset}]] c foo #make the length an unsigned integer set length [expr {${foo} & 0xff}] if {${length} > 0} { #grab a part and put it in our text QNAME section append name [string range [DATAGRAM::udp payload] [expr {${offset} + 1}] [expr {${offset} + ${length}}]] #Watch the DNS QNAME get built during the loop. Remove the following line for production use. log local0.info "BUILDING DNS NAME: [IP::client_addr] queried ${name} offset ${offset} length ${length}" #grab a part and put it in our text QNAME section set offset [expr {${offset} + ${length} +1}] #endlength contains the Last part length binary scan [string range [DATAGRAM::udp payload] ${offset} ${offset}]] c foo #make the length an unsigned integer set endlength [expr {${foo} & 0xff}] if { ${endlength} > 0} { #put a dot between parts like a normal DNS name append name "." } incr i } } #/extract QNAME from QUESTION header #Input the required action here, where "${name}" is the variable that is reviewed for decision making. #Sample action would be a pool statement. The below log statement should be removed for production use. log local0.info "FINAL DNS NAME: [IP::client_addr] queried ${name}" } Tested this on version: 12.1
