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Forum Discussion

Livius's avatar
Livius
Icon for Cirrus rankCirrus
Mar 08, 2018

RESOLV::lookup questions

Hi everyone,   I'm using an irule where I use RESOLV::lookup to determine the destination for ongoing connections. I have some concerns about a failure scenario where the FQDN could not be resolv...
application delivery
LTM
JG's avatar
JG
Icon for Cumulonimbus rankCumulonimbus
Mar 08, 2018
 Put lookup result in a list:

set addr_list [RESOLV::lookup @8.8.8.8 -a example.com"

 Check if there is any entry found:

if { [llength $addr_list] > 0 } {
    foreach addr_found $addr_list {
         Do something.
    }
} else {
     No entry found.
}

See https://devcentral.f5.com/wiki/irules.resolv__lookup.ashx, which also answers your questions about result caching.