Author: James Saunders Date: Tue, 28 Jun 2005 14:51:00 CEST
Cisco released two different batches of Catalyst 2924XL, each with different memory configurations:
- 4 MB DRAM switch with 2 MB of Flash
- 8 MB DRAM switch with 4 MB of Flash
When Cisco originally released the Catalyst 2924 switch it was manufactured with only 4MB of DRAM and no support for VLAN trunking. Due to customer demand Cisco soon released the same switch with 8MB of DRAM to support the larger IOS version 12 images, and also added hardware support on switch ports for VLAN trunking.
The older 4MB DRAM version of the switch is in low demand these days, due to it’s hardware limitations and it’s inability to support any newer IOS image above 11.2.8-12(SA6), nobody really wants one and they are hard to sell. This is where I got stung! Cisco in their infinite wisom decided that they would not give the newer 8MB DRAM switch a new model number but keep it exactly the same as the old model, and so the model number “WS-C2924C-XL-EN” could relate to either 4MB or 8MB DRAM versions of the switch, and as a result looking at a stock list there is no way to differenciate between the two versions. I purchased one on ebay, unaware of this, I ended up with an old 4MB DRAM version which was as mush use to me as a chocolate tea pot, because I needed VLAN trunking support.
But there is hope! There are a few ways you can tell the difference between the two different switch versions.
1. Physical Size
The first obvious difference you will see when looking at the two switches side by side is the size of the units. The older 4MB version is much longer, this can also cause issues when trying to fit it into a rack which does not go very far back. The measurements of the switchs are as follows:
|2924 Version||Dimensions (H x W x D)|
|Older with 4MB DRAM||1.73 x 17.5 x 13.5 in. (4.4 x 44.5 x 33.0 cm)|
|Newer with 8MB DRAM||1.73 x 17.5 x 9.79 in. (4.4 x 44.5 x 24.8 cm)|
2. Port Numbering
A second way to tell the two switches apart is the way in which Cisco has printed the numbers above each switch port. On the older 4MB DRAM version, the numbers are moulded or embossed into the plastic front plate above each switch port. The newer 8MB DRAM version’s port numbers are simply printed in yellow above each port and are not moulded, see the image below for an example:
Even a blind man could tell the difference between the two version by using his fingers!
3. “show version” Command
The third way is if you have access to the switch by console or telnet, you can see the amount of memory the switch has by using the “show version” command:
Older 4MB DRAM Version
switch1#sh ver ..... System image file is "flash:c2900XL-hs-mz-112.8.12-SA6.bin", booted via cisco WS-C2924-XL (PowerPC403GA) processor (revision 0x11) with 4096K/640K bytes of memory. Processor board ID 0x07, with hardware revision 0x00 .....
Newer 8MB DRAM Version
switch2#sh ver ..... System image file is "flash:c2900xl-c3h2s-mz.120-5.WC11.bin", booted via cisco WS-C2924-XL (PowerPC403GA) processor (revision 0x11) with 8192K/1024K bytes of memory. Processor board ID FAB0438U050, with hardware revision 0x01 .....
note: No matter how hard you try, you can NOT upgrade the IOS image of an old 4MB DRAM switch above 11.2.8-12(SA6) due to the fact that any newer IOS images will not run on 4MB of DRAM and will not fit on the 2Mb of flash. There is NO way to upgrade the memory of the unit, therefore the highest image you can put on the 4MB DRAM version is “c2900XL-hs-mz-112.8.12-SA6.bin”.
You also can NOT add VLAN trunking support to the old 4MB DRAM version, firstly the IOS image does not support it and secondly the hardware port controllers physically do not have the capability for it’s ports to be VLAN trunk port enabled.