[cisco-nas] high cpu load on LNS

[Dennis Peng]

Anastassios Chatzithomaoglou [achatz at forthnet.gr] wrote:
> 
> 
> Dennis Peng wrote:
> 
> >Tassos Chatzithomaoglou [achatz at forthnet.gr] wrote:
> >
> >>After reading "High CPU Utilization on Cisco Routers Used as L2TP 
> >>Termination Points"
> >>http://www.cisco.com/warp/customer/794/l2tp_highcpu.html on CCO, i still 
> >>have one question:
> >
> >
> >Please ignore this doc. Read this one instead:
> >
> >http://www.cisco.com/en/US/tech/tk801/tk703/technologies_tech_note09186a0080094c4f.shtml
> >
> >
> >>If i lower the MTU of the LACs (as the document says), will it affect 
> >>normal users (no vpdn ones) too? If yes, in what way?
> >
> >
> >Changing the MTU on the vtemplate will modify the MRU the LAC
> >advertises to the LAC. However, most clients will completely ignore
> >the MRU that is negotiated. For the ones that do (WinXP is one such
> >client), it will decrease the MTU of the client to match the MRU of
> >the LAC.
> >
> 
> After reading the above doc, i'm still confused about what would be the 
> best solution that will work with EVERYTHING. Is it "TCP MSS"?

That's because nothing works with *everything*. :) If you mostly have
TCP traffic, adjust-mss works great. If you have mostly WinXP clients,
tuning the mtu works great. You could do also do both. To do MTU
tuning, CSCdx39828 would be really nice to have as well, so if you'd
like to see up implement it, please open up a case and have the
engineer link it to the bug. Thanks!

Dennis

> 
> >Dennis
> >
> >
> >>-- 
> >>***********************************
> >>  Chatzithomaoglou Anastasios
> >>Network Design & Operations Center
> >>         FORTHnet S.A.
> >>     <achatz at forthnet.gr>
> >>***********************************
> >>
> >>_______________________________________________
> >>cisco-nas mailing list
> >>cisco-nas at puck.nether.net
> >>http://puck.nether.net/mailman/listinfo/cisco-nas
> >
> >
> 
> -- 
> ***********************************
>    Chatzithomaoglou Anastasios
> Network Design & Operations Center
>           FORTHnet S.A.
>       <achatz at forthnet.gr>
> ***********************************

-- 
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      ||        ||                                 Dennis Peng
      ||        ||        Cisco Systems, Inc.      Escalation Engineer
     ||||      ||||       170 West Tasman Drive    Phone: (408) 526-6143
 ..:||||||:..:||||||:..   San Jose, CA 95134       Fax:   (408) 232-2343
   Cisco Systems Inc.                              dpeng at cisco.com
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