neophob.com

If your SSH Ses­sion dis­con­nect even if you enabled “Send­ing of null pack­ets to keep ses­sion active” and “Enable TCP keepalives (SO_KEEPALIVE option)” you might want to try this:

From the Putty FAQ:
On Win­dows NT, 2000, or XP, the reg­istry key to cre­ate or change is
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpip
Para­me­ter­sTcp­Max­DataRe­trans­mis­sions
and it must be of type DWORD. (See MS Knowl­edge Base arti­cles 120642 and 314053 for more infor­ma­tion.)
Set the key’s value to some­thing like 10. This will cause Win­dows to try harder to keep con­nec­tions alive instead of aban­don­ing them.

Descrip­tion of the reg­istry key:

Tcp­Max­Con­nec­tRe­trans­mis­sions
Key: Tcpip­Pa­ra­me­ters
Value Type: REG_DWORD — Num­ber
Valid Range: 0 — 0xFFFFFFFF
Default: 3 (in Win­dows NT)
Default: 2 (in Win­dows 2000)
Descrip­tion: This para­me­ter deter­mines the num­ber of times TCP will retrans­mit a con­nect request (SYN) before abort­ing the attempt. The retrans­mis­sion time­out is dou­bled with each suc­ces­sive retrans­mis­sion in a given con­nect attempt. The ini­tial time­out value is three seconds.

If this does not work for you, you could start for exam­ple top (top –d 2, delay 2s) which should have more or less the same result.