GigaStack GBIC: 2Mbit/s + Fullduplex?

[FmSkt402]

Hi all,

I connect 2 Switches (Type Cat 3550-48) by using GigaStack GBICs (WS-X3550-XL).

The result of using ONE single cable is 1Mbit/s Fullduplex, using TWO cables (without changing the configuration) it changes to 1Mbit/s HALFduplex.

So far so good, that’s exactly what I found in Cisco documentation.

If I understand this docs right, it is possible to build a 2Mbit/s Fullduplex-connection by using two cables.

Who knows how exactly to configure this?

I only found the sub-interfaces Gi 0/1.1 and Gi 0/1.2 and those seem not to be the right ones to create a port-channel.

Can anybody help? Thanx

Rolf Fischer

[milan.kulik]

Hi Rolf,

I think the only way to build 2Mbps full-duplex connection vai Gigastack GBICs is following:

1)You need two GBICs in each switch (i.e. you need 4 GBICs).

2)Connect two stacking cables between switches (i.e. you will use only one port on each GBIC). You get two full-duplex lines.

3) Configure Etherchannel group containing both ports on each switch. I always thought Etherchannel was not supported on Gigastack ports, but the documentation says: "The two Gigabit Ethernet ports on each Catalyst 3550 Series switch can be grouped together using Gigabit EtherChannel® technology to create a stack connection with a full-duplex 4-Gbps forwarding rate." See http://www.cisco.com/warp/public/cc/pd/si/casi/ca3500xl/prodlit/gbic_ds.htm

and

http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/29_35wc6/scg/swports.htm#xtocid18

for details.

Regards,

Milan