Dropping packets on WAN facing interface, looking for options

[poulid.cma]

We're experiencing some dropped packets on the port that uplinks us to the provider CE (outdiscards) on our core 6500. The blade is a WS-X6748-GE-TX. We suspect that the drops may be due to high utilization (bursty traffic), and the fact that the small buffers on the ports in the WS-X6748-GE-TX simply can't keep up.

We're looking at some options to over come this, namely these;

1:) Add a SIP/SPA combo to the 6500 (7600-SSC-400 with a SPA-5X1GE-V2), and use that to connect our core 6500 to the provider CE (gigE)

2:) Install our own router (preferably a small ASR) between our core 6500 and the provider CE.

3:) Install some intermediary switch between our 6500 and the provider CE that has larger buffers (3850?)

Any advice?

[Joseph W. Doherty]

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Posting

#3 - Unsure the 3850's buffers are all that much larger.  Perhaps with buffer tuning (supported on 3850[?], like on 2960/3560/3750) it might be workable.  Assume you would have 10g link to switch.

Perhaps even better would be some of the small MetroE switches.

#2 - A "large" 4K router should be able to deal with a gig uplink, but assuming you need a 10g link to it, you're forced into an ASR.

#1 - That should be better than the 6748.  Even better might be the 7600-SSC-600.

If price isn't an issue, I would recommend the SPA-600.  If price is an issue, I would look at the some variation of #3.  Might even be a L2 switch.

[poulid.cma]

I don't suppose anyone knows what size the port buffers are on the 3850, do they? I can't seem to find anything specific.

A 'large' 4K router is about the same price as a small ASR, and we only uplink at 1Gb. 

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Again, the issue with a 4K router would be how do you get the data to it?

If your issue is the uplink is on the 6748, and you move it to a 4K, what interconnects your 6500 and the 4K?  If you continue to use a 6748 port, you'll like still have the same issue.  (An alternative might be to have an etherchannel between the 6500 and the 4k [or another network device].)

ASR1Ks will support 10g interfaces, which would be the ideal way to interconnect your 6500 and the ASR.  Of course, this also assumes you already have 10g ports on the 6500.

[poulid.cma]

I guess my thought was that an ASR (or a 4K) would have horsepower/buffer space to deal with an minor congestion issues, without dropping the packets. We've got 10g interfaces in the 6500.