Hi,

Maybe this might help....(it fixed a problem I was having on some Raspbian based systems)..

I don't think it is xymon specifically related... probably due to the OS upgrade....

Although the link below is debian related I think it might be an issue with new/older versions of ssh(d)... the intergooglenet isn't clear, but it fixed my issue... (setting IPQoS 0x00)

https://wiki.debian.org/SSH#SSH_hangs

Hope this helps...

Frank