ssh to another server from opnsense may take sometimes till 30 seconds

[devhunter55]

Hi all

i've got a strange behave on Opnsense  - when ssh to another server (which is configured in UNBOUND DNS),
ssh connection takes sometimes up to 30 seconds - but not always.

Most of the time the ssh connects very quickly, but sometimes there is a huge wait.

I.e. opnsense# ssh server1

Did run the command (ssh server1) with debug option, i see these messages:

debug3: verify_host_key_dns
DNS lookup error: general failure

The "DNS lookup error: general failure" appears also, when the ssh connection is quick, so i think this not the culprit here.

nslookup of server1 is always very fast  (means, the server can be resolved by DNS).

cannot find any relevant information into the logs ..

[devhunter55]

Versions    OPNsense 22.1.1_3-amd64
FreeBSD 13.0-STABLE
OpenSSL 1.1.1m 14 Dec 2021

[devhunter55]

(the huge wait appears always after the message "debug3: verify_host_key_dns")

[devhunter55]

(i do not see this behave, when doing a ssh connetion from another server to server1)