FAILED selecting pool based on DNS reverse lookup result.

Thanks for your answer!

I tried below:

-----
when CLIENT_ACCEPTED {
    set ptr [RESOLV::lookup @ inet -ptr [IP::client_addr]]
    if { $ptr ends_with ".jp" } {
        pool SMTP_AUTH_Pool
        log local0. "selected SMTP_AUTH_Pool ptr = $ptr"
    } else {
        pool SMTP_Fallback_Pool
        log local0. "selected SMTP_Fallback_Pool ptr = $ptr"
    }
}
-----

but $ptr was empty although I tried with IP address which should be reverse lookuped.

There is a known issue "sol12378: The 'RESOLV::lookup -ptr' iRule command fails to return a valid hostname ", so I think is does not work. (Our BIG-IP version is 10.2.1 297.0)

Is there a way to use NAME:: method instead of RESOLV:: method ?

thank you for your help!