Forum Discussion

MustphaBassim's avatar
Mar 04, 2024

Adding Node by FQDN

Hello Dears

Could we add node by FQDN using * for exmple :

 

*.f5.com 

so any subdomain would be includes ?

 

Bests 

3 Replies

  • What would you hope that would happen @MustphaBassim?

     

    Like if you add *.f5.com then it would add all servers below that? Like www.f5.com and ftp.f5.com and api.f5.com and ...?

     

    That is for sure not going to happen because there is no way to actually do a DNS lookup which reveals everything that exists under f5.com. 

  • MustphaBassim in theory this would work because it is technically an acceptable DNS entry on an authoritative NS. Now I do believe the LTM would not allow this because this could resolve to any number of records such as MX, TXT, A, CNAME, and so on. This could be a valid entry if what returned was an A, AAA, or CNAME but anything else would not work because it does not resolve to an IP address. I'm with Michael_Saleem on this one that it probably cannot be configured. Additionally, I don't recommend using FQDNs as pool members because it means that on the F5 side of things you cannot manually disable pool members if that one FQDN resolve to multiple IPs. Now if you rely on monitors that use the "receive disable" function then this would put this on the server side to disable themselves but typically this is not the case.