adding pool members dynamically without DNS resolution.

[thomasevig]

Hello dear forum users,

we're using F5  Big-IP and we need to find a way

of adding members to a pool (from the 

same ip range of course)  dynamically without 

having to add each member manually all the time. 

for instance, if a new server/instance has been configured, instead of adding a member 

one by one, we need to have it added without our intervention. 

please let me know if there's a way of doing so. 

thanks in advance (:

[Nikoolayy1]

How did you not found this article as F5 can do this is in a long time and it is a popular feature:

https://community.f5.com/t5/technical-forum/pool-members-with-fully-qualified-domain-names-fqdns-how...

[thomasevig]

Hi thanks for the reply, 

but i'm searching for a solution without having to use FQDN's. 

[Nikoolayy1]

Then maybe go with REST-API and Ansible as F5 has modules for Ansible and even a training or if you have BIG-IQ you can use the BIG-IQ script option to run from time to time:

https://clouddocs.f5.com/training/community/big-iq-cloud-edition/html/class5/module1/lab6.html

[AubreyKingF5]

Just a thought.. F5 Distributed Cloud has pool members by name, natively, just due to the number of times we need that feature in the cloud or containered environments. If you haven't checked out F5 XC, please do. It can run in your data center side-by-side with LTMs and can easily have traffic - even internal - driven to it via GTM.. er.. F5 DNS.

[StephanManthey]

Why not using the REST API to add the new server to the pool? I guess you are using some automation to setup your servers, right?

POST /mgmt/tm/ltm/pool/~<partition-name>~<pool-name>/members

{"name":"node_121:80","address":"10.131.131.121",
"session":"user-disabled","partition":"Common"}

will do the job (using a basic or token based auth)

DELETE /mgmt/tm/ltm/pool/~<partition-name>~<pool-name>/members/~<partition-name>~<node-name>:<port>

will remove it, when the server is going to be taken down.

In any case make sure to save the config to the startup config, because the API will modify the running config only.

[AubreyKingF5]

Could also "script it" by using an EAV monitor. Your EAV script can do ANYTHING on box - including an nslookup and tmsh modify based on results of the nslookup.