[j-nsp] SSH/Telnet session hanging

[Muhammad Adnan Mohsin]

Dear Alexander,
I have found that the maximum PING size is 1870. If the value is 1871
I get a message "ping: sendto: Message too long". But at size 1870...I
am getting ping drops. The success rate is around 60%. Is it normal to
get ping drops? Anyways I have set the MTU to 1870+28=1898 and still
observing the BGP sessions.

regards,
Adnan.

On Wed, Jun 1, 2011 at 1:53 PM, Alexander Frolkin <avf at eldamar.org.uk> wrote:
> Hi,
>
>> I have resolved the session hanging issue by lowering the MTU value to
>> 1920 on this router. But the BGP session is now flapping a lot and
>> it's flapping with both the RRs now. Should I try the tcp-mss option
>> or should i further play with the MTU value. I lowered the value to
>> 1800 but the flapping was still there. Should I lower this further?
>
> If it helps, you can use ping to find out the MTU.  On JunOS:
>
>  ping <hostname> size 1472 do-not-fragment
>
> On Linux:
>
>  ping -M do -s 1472 <hostname>
>
> Increase the size until the pings fail.  The MTU is then the maximum
> ping size plus 28.
>
>
> Alex
>
>