Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Chassis Line cards

Hello,

I am preparing to purchase a Chassis and Line Cards for a site Network upgrade. Since this site happens to be our datacenter with our servers and also have about 200 client connections coming in, I was planing on purchasing two Chassis's and then installing 10GB and 1GB line cards (with POE+ on the 1Gb) so I could collapse all those connections into the two chassis.

I was talking to a vendor and he said that its not recommended that client connections be in the same chassis as your Core and that those connections should be on seperate switches that are uplinked to the core.

That seems like a waste for me as all devives in the chassis can be covered under one smartnet which saves quite a bit of money.

Does anyone have any thoughts on this? Does anyone out there have thier client line cards in the same chassis as the core.

Thanks,

Kevin

Everyone's tags (3)
1 ACCEPTED SOLUTION

Accepted Solutions
Super Bronze

Chassis Line cards

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

You vendor is making a good recommendation.  Reason for the recommendation is to avoid having edge device instability upset the core of the network.

However, although the recommendation is good, as you've noted, it adds cost.  So the real question is, risk vs. cost.  Unfortunately, calculating risk can be extremely difficult, especially the likelihood of something happening.  Then you need to also calculate cost of a failure.  Compare to cost to avoid, and place your bet.

6 REPLIES
Super Bronze

Chassis Line cards

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

You vendor is making a good recommendation.  Reason for the recommendation is to avoid having edge device instability upset the core of the network.

However, although the recommendation is good, as you've noted, it adds cost.  So the real question is, risk vs. cost.  Unfortunately, calculating risk can be extremely difficult, especially the likelihood of something happening.  Then you need to also calculate cost of a failure.  Compare to cost to avoid, and place your bet.

New Member

Chassis Line cards

Please explain how can you be sure that the problem the edge device is having wouldnt reach the core if its not connected via a line card on the same chassis. The switch that connects to the device is going to be uplinked to the core anyway so what difference does that make?

Hall of Fame Super Gold

Re: Chassis Line cards

Please explain how can you be sure that the problem the edge device is having wouldnt reach the core if its not connected via a line card on the same chassis. The switch that connects to the device is going to be uplinked to the core anyway so what difference does that make?

If your core goes down, so does everyone.

If you separate your core and access switch, then your access switch goes down, SOME of your clients can work.

Besides, in regards to maintenance some selected Cisco Catalyst switches have Limited LIFETIME warranty.

Super Bronze

Chassis Line cards

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

Kevin McDonald wrote:

Please explain how can you be sure that the problem the edge device is having wouldnt reach the core if its not connected via a line card on the same chassis. The switch that connects to the device is going to be uplinked to the core anyway so what difference does that make?

You're correct, having another device between the edge device and the core device doesn't 100% guarantee some problem can't still be "forwarded" into the core, just makes it a little less likely especially if the device(s) attaching to the core are L3.

For example, consider a L2 loop.  Such might overrun the capacity of the device the loop is formed on.  So, better it be an edge device rather than your core device.

Again, this is logic for the separation, but I'm not suggesting you always must separate devices.  Much risk can be mitigated, as for example with L2 loops that's a reason to run a STP even when you don't have intentional L2 link redundancy.

New Member

Re: Chassis Line cards

Couldnt I just use L3 line cards in the Chassis and get the same effect as having a seperate switch?

Thanks for the replies!

Kevin

Super Bronze

Re: Chassis Line cards

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

Kevin McDonald wrote:

Couldnt I just use L3 line cards in the Chassis and get the same effect as having a seperate switch?

Thanks for the replies!

Kevin

That would likely depend on the chassis and line card - might be true with a platform that performs distributing processing.

301
Views
0
Helpful
6
Replies