ERS 3500 fiber ring 1

[gknight1]

We have a customer that currently has 4 buildings on their property with fiber going to them all jumping from building to building, each one connected to a 3524GT-PWR via GBIC. The customer is adding another building looking to complete a fiber ring around the property. Right now I just have all the VLANs tagged on the ports that have the fiber plugged in. How do I program the 2 ports that will be connecting the fiber ring to prevent a loop? Do I need to change how the ports are currently programmed on the uplink ports now?

Not sure exactly what version the switches are on, think most of them are 5.2.0.004 I can upgrade if needed.

I know this inst the ERS forum (which I posted as well), but I figured half you guys probably use the ERS as well. Any help is greatly appreciated.

 

[atcom]

Good question, I'm afraid I don't know specifically but it must be possible to do because Avaya is always talking about how their "Active/Active" setup is better than Cisco's Spanning Tree Protocol. If it was a Fabric switch like a 4800 I think it would just take card of the ring automatically...

-----------------------------------

Calgary Telephone Systems, Avaya LG Asterisk (FreePBX) VOIP & TDM

 

[gknight1]

the research that i've done has led me to lacp or vlacp, but not very confident in my findings to be able to implement anything yet.

 

[derfloh]

I think with 3500 the only way will be RSTP. It needs much less time than standard STP to rebuild the tree.

 

[amriddle01]

There is an Avaya/Nortel networking forum on here, I can't link it as I'm on my phone, but have a try in there too

 

[derfloh]

He got no answer there. The networking forum is not very active.

I think here

https://forums.networkinfrastructure.info/nortel-ethernet-switching/

is the better place for Avaya networking questions.

 

[gknight1]

thanks, I posted there, looks like rstp will be the way to go, now just have to figure out how to program... any pointers? it looks like stp is enabled by default already, so should I just be able to change the mode from stp to rstp and be done?

 

[Westi]

What I know about the switches it will find the fastest way from the source to the destination so if you enable RSTP (Rapid STP) it will help in case a packet gets lost and prevent downtime for more than a couple of seconds on that path but that should never happen as the switches learn what route to take as fastest way.
So much for the sales document of the switches but we all know that Avaya is not to exact with those.

Joe W.

FHandw, ACSS (SME)


"This is the end of the world, make sure to buy your T-shirt before it is too late"
Original expression of my daughter

 

[AvantiWade]

RSTP is what you are after,

https://downloads.avaya.com/css/P8/documents/100161568

Page 99 is the commands. RSTP elects a master and all other switches will forward or block traffic out of their uplinked ports based on their position to the master switch to prevent loops.

LACP is not applicable in this case, think of it as turning 2 physical links into 1 logical link. If you had 2 fiber cables between each building and wanted to form them into 1 logical link you would enable this on both switches.

 

[derfloh]

But with only AVAYA switches you would use MLT instead of LACP. But that is not what you need in your case.

 

[gknight1]

so from my reading i need to...

change the spanning tree admin mode from the default of stg to rstp?

so i would set all ports except my fiber ports (ports connecting all the switches) to edge ports?

how do i set the main switch as the master?

 

[AvantiWade]

I'd watch a video on Spanning tree on youtube to get a better feel for what you are doing. Any of the CCNA Spanning Tree /Rapid Spanning Tree videos should work.

You can influence the election process by changing the Priority of the switch to a lower number. Lowest Priority will be elected master, if there is a tie it will go off of the lowest mac address of the switch ports.

I don't work with avaya's switches much but from what I see in that manual I linked above you would do something like:

spanning-tree mode rstp
spanning-tree priority 0x1000

That will set the switch to rstp mode and a priority value of 4096. God knows why they make you put the priority in hex but whatever.

Other switches would be:

spanning-tree mode rstp
spanning-tree priority 0x2000

That sets them with a priority of 8096.

That is the most basic config you could set up, there is a lot more to it that you will want to learn and tune.

 

[gknight1]

thanks wade, you got me in the direction i needed to go.