Re: bgp pmtud

No the DF bit is not set, use the tcp ip adjust to ensure the DF bit is set.

Regards,
 Joe Sanchez

( please excuse the brevity of this email as it was sent via a mobile device. Please excuse misspelled words or sentence structure.)

On Nov 1, 2012, at 8:51 AM, Imran Ali <immrccie_at_gmail.com> wrote:

> Hi all,
>
> By default when bgp router sends update ...does it sets DF bit ?
> question 1
>
> in this case if the size of update packet let say is larger than
> MTU of any of transit links ..then any transit router upon reception of
> DF marked bgp update packet send an ICMP error , if icmp is filtered due
> to any firewall then originating router will not reduce the MSS and this
> results in oscilaitng bgp sessions
>
> http://nagendrakumar-nagendra.blogspot.com/2010/03/bgp-path-mtu-discovery.html
>
> does any one have experinced the same or can comment on this ?
>
>
> 2) if bgp path mtu is enabled by default ..then do the router undergo
> path mtu discovery ..and figures out lowest mtu of transit links and then
> adjusts the [mss = lowes mtu - (ip headers) - (tcp headers) ] ..?
>
>
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Received on Thu Nov 01 2012 - 13:55:05 ART