Re: SDH Fiber Problem

[jacob miller <mmzinyi () yahoo com>]

Managed to solve this problem.

It was MTU related as my routers had an MTU size set at 1600.

Removed this setting from both ends and managed to get traffic flowing.

Had earlier terminated a laptop at one end of the link just to test and found I was able to push more than 20MB.

Thanks for your assistance on this.

Regards,
Jacob Miller


----- Original Message -----
From: Leigh Porter <leigh.porter () ukbroadband com>
To: jacob miller <mmzinyi () yahoo com>
Cc: "nanog () nanog org" <nanog () nanog org>
Sent: Monday, September 19, 2011 11:17 AM
Subject: Re: SDH Fiber Problem

It does sound like an MTU issue. Symptoms are typical. Did you try pings end to end with DF bit set and full size 
datagrams?



-- 
Leigh Porter


On 19 Sep 2011, at 09:15, "jacob miller" <mmzinyi () yahoo com> wrote:

> By meanigful traffic I mean traffic like Http traffic
>
> Am able to ssh no problem.
>
> Most of the clients on the link are using it for browsing.
> However we find that even though they are able to resolve and ping different sites.
> When it comes to opening of the page we have the page reading as opening opening .. but the page never gets opened.
>
> Regards,
> Jacob Miller
>
>
>
> ----- Original Message -----
> From: Leigh Porter <leigh.porter () ukbroadband com>
> To: jacob miller <mmzinyi () yahoo com>
> Cc: "nanog () nanog org" <nanog () nanog org>
> Sent: Monday, September 19, 2011 11:10 AM
> Subject: Re: SDH Fiber Problem
>
> What exactly do you mean by meaningful traffic? ICMP from port to port works, can you pass TCP? SSH between routers? 
> Establish a TCP session over it?
>
> Are you using Juniper SRXs ? :-)
>
> -- 
> Leigh Porter
>
>
> On 19 Sep 2011, at 08:24, "jacob miller" <mmzinyi () yahoo com> wrote:
>
> > I have tried the pings and am able to ping through with a size of 1600 with the df-bit set
> >
> > without the df-bit am able to get up to 9000.
> >
> > The switched on bot ends hav been set to allow jumbo frames through and the system MTU size and routing MTU sizes 
> > are at 1998.
> > The switch is a 2960 Cisco switch.
> >
> > I have set the mtu on the interface on the end router to 1600 and still unable to push meaningful traffic.
> >
> > Regards,
> > jacob Miller
> >
> >
> >
> > ----- Original Message -----
> > From: Randy Bush <randy () psg com>
> > To: jacob miller <mmzinyi () yahoo com>
> > Cc: "nanog () nanog org" <nanog () nanog org>
> > Sent: Monday, September 19, 2011 9:55 AM
> > Subject: Re: SDH Fiber Problem
> >
> > > I can ping on point to point
> > > I have BGP up and running
> > > When I try to pass traffic over the link my clients are unable to pass
> > > any meanigful traffic asn browsing is impossible.
> >
> > mtu?  try various size pings.
> >
> > filters?
> >
> > randy
> >
> >
> >
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