[c-nsp] "Core/AGG" switch for small DC

[Blake Dunlap]

I wouldn't ever do a stackable for a core, that is just asking for
down time for various scenarios for no appreciable reason. If anything
the 4948 is an upgrade for the 3xxx gear. I would also suggest either
the X or the n5600 like two previous suggestions, with leanings to the
n56 depending on what you're doing. (Need for exotic multicast or mpls
are big red flags).

Also, I personally hate VSS in the core. Independent control planes is
a good thing if you care about redundancy. It's fine in dist, but I'd
be weary of it in core without a really good reason.

The above are just my personal suggestions though, the best thing to
do is if you don't know yourself is to hire someone who does on a
contract basis to design it, and have them document the reasons and
educate you in the process.

-Blake

On Thu, Mar 26, 2015 at 12:53 PM, CiscoNSP List
<cisconsp_list at hotmail.com> wrote:
> Thanks very much for the info....got a couple of 4500X's(In VSS, and hasnt missed a beat in 2years), and I do like them...but price is getting up there...same with the Nexus kit...never used them, and would be a nice option to go with what you have described...just would mean replacing all the existing 4948's...unfortunately not an option at this stage :)
>
> Ill re-check the 4500X's price....havent bought one in over 2 years, so I may be pleasantly suprised ;)
>
>
>
>
>> Date: Thu, 26 Mar 2015 14:24:19 -0500
>> From: brez at brezworks.com
>> To: cisco-nsp at puck.nether.net; p.mayers at imperial.ac.uk
>> Subject: Re: [c-nsp] "Core/AGG" switch for small DC
>>
>> On 3/26/2015 11:35 AM, CiscoNSP List wrote:
>> >> For a datacentre, I'd pay attention to buffering. Cisco stackables tend
>> >> to have tiny buffers (not sure about 3950), which may or may not be a
>> >> problem for an agg switch, depending on your traffic patterns and link
>> >> speeds, and whether the device does cut-through switching.
>> >>
>> >> How many ports and of what media/speed do you want? Do you need any DCB
>> >> / FCoE stuff? Layer 2 or layer 3?
>> >
>> > Purely L2, all eth...Id like 2 separate agg boxes, but dual links from TOR switches, to 2 "independent" switches would be difficult (i.e. how to have all vlans go to both switches, and handle a failure of one of them "automatically"...all the cust vlans are trunked up to ME's and ASR's for L3.
>> >
>> If you've been happy with the 4948s, I'd look at the 4500X as a possible
>> aggregator for them.  16/32 ports of 1/10G (plus 8 on an expansion
>> module), support for all the optics and twinax options (with a few
>> caveats for ZR optics, but shouldn't be an issue within a DC).
>>
>> They do support VSS, and it's been stable for us for ~18 months running
>> 10 floors worth of heavy users from closet 4507R+E's via 20Gb
>> port-channels as well as a large port-channel via EWDM boxes to our
>> data-center.  Mixed L2/L3 on ours, and other than having to order some
>> 3rd party PDU cables (C15s on these, not C13s, same as the PoE 3560X's)
>> they've been great for our use case.  We've got another pair running in
>> a colo space for circuit handoffs, and they've been rock solid boxes for
>> us.  They're basically a Sup7E from a 4500E with 16/32 ports of 10G
>> built into a 1U chassis, same code image and feature support as you'd
>> have on those.
>>
>> The other option for a more traditional data-center switch would be the
>> Nexus 5500/5600 lines.  These are NX-OS rather than the IOS-XE of the
>> 4500X so there is a learning curve there if you aren't familiar with it,
>> but are 90% of the functionality you'd get out of a Nexus 7000/7700
>> device in a 1-3U package.  The 5500/5600s do VPC which allows you
>> dual-active forwarding and are a cut-through instead of traditional
>> store and forward switch.  The 5600s also have 40Gb ports available and
>> would allow you to use FEX's to replace some of the TOR 4948s and have
>> all management from one central point (can configure master/slave for
>> configs on the 5Ks in VPC mode, so you configure both switches as one
>> unit, same with VSS on the 4500X's).  The 5500/5600 are more limited on
>> their optics support (don't support any CWDM/DWDM or ER/ZR optics), but
>> are a solid data-center/TOR switch.
>>
>> I've worked with both of these for several years, let me know if you
>> have any specific questions about either of them.
>>
>> Jeremy "TheBrez" Bresley
>> brez at brezworks.com
>> _______________________________________________
>> 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/
>
> _______________________________________________
> 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/