For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

NN_210021's avatar
NN_210021
Icon for Nimbostratus rankNimbostratus
Aug 03, 2015

Curl perform failed: Couldn't resolve host name (6)

Hi all,   can anyone give me a hint on what causes this error ? Can't find anything on DC /internet search   HTTP module: authenticateUser(): Curl perform failed: Couldn't resolve host name (6)...
Hannes_Rapp's avatar
Hannes_Rapp
Icon for Nimbostratus rankNimbostratus
Aug 03, 2015

To sort out the DNS issues, try to follow the steps below:

 Check to see if you have a DNS server configured
hannesr@(lb01)(cfg-sync Changes Pending)(Active)(/Common)(tmos) list sys db dns.nameservers
sys db dns.nameservers {
    value "10.199.22.2 10.199.22.6"
}
hannesr@(lb01)(cfg-sync Changes Pending)(Active)(/Common)(tmos) q

 Check to see if you have DNS server connectivity
[hannesr@lb01:Active:Changes Pending] config  dig blabla
; <<>> DiG 9.9.6-P2 <<>> blabla
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 58826
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;blabla.                IN  A

;; AUTHORITY SECTION:
.           10688   IN  SOA a.root-servers.net. nstld.verisign-grs.com. 2015080300 1800 900 604800 86400

;; Query time: 1 msec
;; SERVER: 10.199.22.253(10.199.22.2)
;; WHEN: Mon Aug 03 12:08:38 UTC 2015
;; MSG SIZE  rcvd: 110
Amresh008's avatar
Amresh008
Icon for Nimbostratus rankNimbostratus
Aug 10, 2018

There are two ways in which DNS can be added in F5 and both have different results. If you add it under system tab - that helps your F5 (bash) to resolve the hostname for cURL And if you add it under Network- DNS resolver list,this enables your TMM to resolve the URLs (used in http proxy config.)