Trunking on 5500 series switch 2

[alphaalpha1]

Hi,

I am new to this Forum and also to Nortel as well, If anyone can help me or guide me to proper direction, I would be really thankful to him.

Here is the scenario.

We have around 7 Nortel 5500 series switch. One default VLAN, one subnet.
Sw 1 to 5 are cascaded to each other through SCSI cable. Same with Sw 7 & 8.

Sw 1 & 7 are connected through one ethernet LAN cable.

I need to accomplish:- (Also need your Advice / direction)

Configure Trunking between sw 1-7 & 5-8 by reserving four ports on each switch.

We do not want to create VLANs at all.

I also read somewhere instead of Trunking, configuring Ethernet access port is better bet.

So guys you tell me what is best way and how to achieve that.

Thanks in advance.

 

[andy88]

Its simple to do. Just leave the default vlan as it is.

Then go on to the menu of the stack. go to config mlt and add the ports you want in the trunk (up to 8). Then do the same on the other stack. Once done just plug the cables in. You will have a working trunk between the stacks.

 

[DaddyOfThree]

You don't even have to make any configuration changes if your just going to be using VLAN 1 (Default VLAN). Just connect each stack to the next with a single CAT5/CAT6 cable.

Out of the box Spanning Tree Protocol should be enabled so that will help prevent you from putting a loop in your network.

Cheers!

 

[alphaalpha1]

Thanks both of you for your response and time.

Daddy of three :- I already mentioned that we do have present scenario what you suggested, but that is not redundant. Also total load is on one single Cat 5/6 cable.

Andy88:- I read in Nortel TIDs what you mentioned but was not sure, since you suggest the same thing, I think we can give it a shot. Is there any drawback you experienced in this scenario..?

Thanks again for both of you.

 

[DaddyOfThree]

If you want redundancy (multiple ports?) you'll need to setup a MultiLink trunk group. You can leave the ports as "Access" or set them up as "Trunk" it doesn't matter with one VLAN unless you want 802.1p bits (QoS) to be preserved between the switches then you need to use a "Trunk" port.

Good Luck!

 

[anthonyanderberg]

The only problem I've ever had with MLT was once upon a time one member of an 8-port MLT bundle started dropping packets randomly (hardware error). The ports didn't register errors and the link didn't go down so it was hard to troubleshoot because it affected (what seemed to be) a random 1/8th of our users. Once I figured out what was happening it was easy to isolate the port, but it was a long afternoon. Having said that I've setup many many MLTs before and since with no issues.

As a side note - MLT uses the same basic scheme as Cisco's Etherchannel.

 

[alphaalpha1]

Perhaps one last question.

As I mentioned earlier, presently both switches are connected through one Ethernet cable. While configuring MLT does it need to remove?
And it could be any port/s of the switch? not necessearly the last or specific one?

Thanks a lot for your patience.

 

[alphaalpha1]

Addition to my previous question.
Do we need cross cable or straight for the MLT?

 

[anthonyanderberg]

The 5510 should auto-cross so a straight cable should work for switch-to-switch links. There are no restrictions on what ports are members of an MLT, although it is recommended that you connect them together in order - the first port in the MLT on one side should go to the first port in the MLT on the other side. You can have an MLT with only one active port, as long as you configure MLT before plugging the other links in you should be fine.

 

[alphaalpha1]

You mentioned in your previous experience you had errors where ports did not registered the error/s.

Wouldn't LACP or VLACP help to identfy those situations..?

 

[anthonyanderberg]

Now they should, at that time LACP wasn't an option...

 

[DaddyOfThree]

As Anthony points out it's best practice to connect the lowest number port on one switch to the lowest number port on the next switch when building a MultiLink trunk.

If you have autonegotiation enabled you shouldn't really have any need for VLACP.

Cheers!