Connecting WS-C2948G to WS-C3524 via GBIC?

[weldingkat]

For our internal LAN, we currently utilize a 48-port WS-C2948G 10/100 switch.  While old, it has served our needs reliably and we intend to retain it in our infrastructure.

Due to the addition of a VOIP server, we purchased a used WS-C3524-PWR-XL-EN switch, which provides 24 10/100 ports, but also provides POE over those 24 ports which we have tested successfully with the phones we have purchased as well.

What we would like to do is connect the two switches so they operate as one "big" switch.  I know we can do that by using an ordinary cat-5 crossover cable however we would prefer to use the 10x faster GBIC ports if possible.  According to various Cisco documentation, the GBIC's that are compatible with both units are: WS-G5483 / 84 / 86 / 87.

My question is this - will these two switches be able to talk to one another via the GBIC ports even though they are of different vintage?

Thank you in advance for any advice and/or comments.

Frederic

[Jon Marshall · Accepted solution]

weldingkat wrote:
For our internal LAN, we currently utilize a 48-port WS-C2948G 10/100 switch.  While old, it has served our needs reliably and we intend to retain it in our infrastructure.
Due to the addition of a VOIP server, we purchased a used WS-C3524-PWR-XL-EN switch, which provides 24 10/100 ports, but also provides POE over those 24 ports which we have tested successfully with the phones we have purchased as well.
What we would like to do is connect the two switches so they operate as one "big" switch.  I know we can do that by using an ordinary cat-5 crossover cable however we would prefer to use the 10x faster GBIC ports if possible.  According to various Cisco documentation, the GBIC's that are compatible with both units are: WS-G5483 / 84 / 86 / 87.
My question is this - will these two switches be able to talk to one another via the GBIC ports even though they are of different vintage?
Thank you in advance for any advice and/or comments.
Frederic

Frederic

There is no reason why you cannot interconnect the switches via the GBIC links so yes you should be fine.

Jon

[weldingkat]

Wow Jon, thank you for your incredibly fast reply and that's great news!  I'll order a pair of GBICs tomorrow once we figure out the media we should use in between the GBIC units.  They're stacked one on top of the other so hopefully we'll figure out which one is cat 5e.  The 5483 I believe is cat 5.

Thanks again!

Frederic

[Leo Laohoo]

WS-C2948G-GE-TX  uses SFP and 3524 uses GBIC.

Q. Which SFP uplinks does the Cisco Catalyst 2948G-GE-TX support?
A. The following SFP uplinks are supported: 1000BASE-SX, 1000BASE-LX/LH, 1000BASE-ZX, 1000BASE-T, and coarse wavelength-division multiplexing (CWDM) SFP uplinks.

Q & A:  Cisco Catalyst 2948G-GE-TX Switch

http://www.cisco.com/en/US/customer/prod/collateral/switches/ps5718/ps606/prod_qas09186a00801cfaef.html

[weldingkat]

Leo, are you sure?  I ask because on this page:

http://www.cisco.com/en/US/docs/interfaces_modules/transceiver_modules/compatibility/matrix/OL_6981.html#wp128965

Both the WS-C2948G and the WS-C3524-PWR-XL-EN switches list some of the same GBIC modules?  Am I looking at the wrong matrix chart?

According to the "show version" command in enable mode, the 2948 displays two modules - one as a WS-X2948 and the second as a WS-C2948G.  I presumed the latter designation was the one to use?

Thanks in advance...

[Leo Laohoo]

Ok, I'm getting absolutely confused.  I am wrong because I thought what you had was the one with SFP.  Didn't realize that you have the earlier version of the 2948.

[weldingkat]

No problem at all Leo!  I welcome the input regardless as all of this makes sure we can order the right parts to make this connection.

After all, my junk drawer is full at the moment ;-)

We're going to order a pair of WS-G5483 GBICs and when they arrive we'll find out if the connection would be straight through cat5e or crossover.  Only two choices so it can't be that difficult!

Thanks again, much appreciated!

Frederic

[Jon Marshall]

Frederic

Just confirm that you are not actually using fiber for connectivity as the WS-G5484 would be the one to use for fiber connectivity ?

Jon

[weldingkat]

I figured since I don't need the distance capability of fiber, since they will be installed one above the other in a rack, a cat-5 connection would be appropriate and less costly than fiber cables and other parts that seem necessary.

The phusical distance between the GBIC ports of the two switches is not even six inches.  A one foot cat-5 cord in a small coil would do the trick, no?

[weldingkat]

Just wanted to update everyone, the Cisco brand GBICs arrived, I connected both switches, and viola, it worked like magic.

thank you all for your help and assistance.  Was far easier than it seemed to be at first.

[Jon Marshall]

weldingkat wrote:
Just wanted to update everyone, the Cisco brand GBICs arrived, I connected both switches, and viola, it worked like magic.
thank you all for your help and assistance.  Was far easier than it seemed to be at first.

Frederic

Thanks for coming back and letting us know it worked.

Always feels good when it just works

Jon