For what are you talking for authentication to the F5 device itself or for authntication of the client traffic when connecting to an f5 VIP?
For authentication of transit traffic to the F5 VS VIP servers have you checked myF5 ? As you see to be able to add more than one servers in the brakets.
ltm auth ldap ldap_config {
search-base-dn ou=Users,dc=askf5,dc=pslab,dc=local
servers { 172.24.171.1 }
}
Also have you tested creating an LDAP VIP with pool and maybe refernce the VIP ip address in the Auth profile or for the F5 GUI in the system tab? You may also use priority groups to use just the first pool member if active:
For the F5 GUI authentication with LDAP: