[c-nsp] MPLS multilink MTU

[Soon Kian]

Hi Rodney

It's works!  after changing physical interface MTU  instead of using "mpls
mtu xxx" I have attached the debug output before and after changing.

Before:
Jul 30 06:07:32.398: Se3/5:0 LCP: O CONFREQ [Listen] id 254 len 23
Jul 30 06:07:32.398: Se3/5:0 LCP:    MagicNumber 0x3C11DFE2 (0x05063C11DFE2)
Jul 30 06:07:32.398: Se3/5:0 LCP:    MRRU 1500 (0x110405DC)
Jul 30 06:07:32.398: Se3/5:0 LCP:    EndpointDisc 1 klp002
(0x1309016B6C70303032)


After:
Jul 30 06:21:53.827: Se4/7:0 PPP: Phase is ESTABLISHING, renegotiate LCP
Jul 30 06:21:53.827: Se4/7:0 LCP: O CONFREQ [Closed] id 28 len 23
Jul 30 06:21:53.827: Se4/7:0 LCP:    MagicNumber 0x3C1F0A9B (0x05063C1F0A9B)
Jul 30 06:21:53.827: Se4/7:0 LCP:    MRRU 1520 (0x110405F0)

Cheers
Soon Kian

On Wed, Jul 30, 2008 at 11:04 AM, Rodney Dunn <rodunn at cisco.com> wrote:

> Soon,
>
> I haven't done this myself but I've seen discussions around
> it before. From what I remember it has to do with the
> MRRU negotiated values.
>
> Check 'debug ppp negotiation' and let's see what
> we negotiated for MRU.
>
> Also, it's best not to use the "mpls mtu" command anymore
> and always set the phsyical MTU on the interface to
> account for the MPLS and/or tunnel overhead.
>
> CSCdj40945
> PPP multilink MRRU value is not configurable
>
> added the support for the:
>
> [no] ppp multilink mrru remote [num]
> and
> [no] ppp multilink mrru local [num]
>
> commands.
>
> See if that helps and let me know.
>
> Rodney
>
>
>
>
> On Wed, Jul 30, 2008 at 10:51:30AM +0800, Soon Kian wrote:
> > Hi Guys,
> >
> > Wondering if any one met with such problem before ?
> >
> > a. Setup: MPLS PE - MPLS PE (using 2 x E1 with mlppp multilink)
> > b. If only 1 x E1 is in bundle, I could ping vrf up to 1500 df. However
> when
> > both E1 are in the multilink, I only could ping up to 1496
> > c. IOS: c7200-jk9s-mz.124-18.bin
> > d. E1 Controller: PA-MC-8E1/120
> >
> > Configuration:
> >
> > interface Multilink11
> >  ip address x.x.x.x
> >  no ip redirects
> >  no ip proxy-arp
> >  carrier-delay 10
> >  mpls label protocol ldp
> >  mpls ip
> >  mpls mtu 1600
> >  no cdp enable
> >  ppp multilink
> >  ppp multilink group 11
> >  no clns route-cache
> >
> > interface Serial1/7:0
> >  bandwidth 2048
> >  ip address x.x.x.x 255.255.255.252
> >  encapsulation ppp
> >  ppp multilink
> >  ppp multilink group 11
> >  no clns route-cache
> >
> > interface Serial2/5:0
> > bandwidth 2048
> >  ip address x.x.x.x 255.255.255.252
> >  encapsulation ppp
> >  no fair-queue
> >  ppp multilink
> >  ppp multilink group 11
> >  no clns route-cache
> >
> > router>sh ppp multilink
> > Bundle up for 19:47:41, total bandwidth 4096, load 42/255
> >   Receive buffer limit 24000 bytes, frag timeout 1000 ms
> >     0/0 fragments/bytes in reassembly list
> >     37 lost fragments, 122838 reordered
> >     632/475896 discarded fragments/bytes, 0 lost received
> >     0x203DB4 received sequence, 0x16EF7F sent sequence
> >   Member links: 2 active, 0 inactive (max not set, min not set)
> >     Se2/5:0, since 19:47:52
> >     Se1/7:0, since 19:47:49
> > _______________________________________________
> > cisco-nsp mailing list  cisco-nsp at puck.nether.net
> > https://puck.nether.net/mailman/listinfo/cisco-nsp
> > archive at http://puck.nether.net/pipermail/cisco-nsp/
>