Forum Discussion

JG's avatar
JG
Icon for Cumulonimbus rankCumulonimbus
Jul 22, 2014

v11.3.0: How to get DNS lookup work in an irule?

I am trying to get an irule to look up a name in DNS. "[RESOLV::lookup -a host_name]" simply times out.   The irule works in v10.2.4 when I enable the BIND server with a forwarder to our dns serve...
APM
application delivery
availability
deployment
devops
iRules
LTM
security
JG's avatar
JG
Icon for Cumulonimbus rankCumulonimbus
Jul 24, 2014

I did this:

 tcpdump -nni 0.0:nnn -s0 port 53

but it did not capture anything, not even the traffic of dig.

 tcpdump -nni eth0 -s0 port 53

This captures the traffic from running dig:

tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
11:55:58.205093 IP 172.21.197.14.50776 > 172.18.240.210.53:  41681+ A? www.sina.cn. (29)
11:55:58.500352 IP 172.18.240.210.53 > 172.21.197.14.50776:  41681 2/2/2 CNAME sina.cn., A 203.90.242.118 (136)

but does not capture any packets when the irule is run.