How to set up a ring topology L2 network?

[timb0]

Hi, I've been trying quite unsuccessfully to have a purposeful L2 loop in my network and to have that part that makes the loop only 'turn on' when there is a drop in another part of the loop.

I would really like some help on how to configure the Netonix switches in this manor. I have upgraded all the switches in our network in order to have this feature..

A simple ring network would look like this: 5 switches all daisy-chained together (makes a ring, right? lets call them numbers: 1 -- 2 -- 3 -x- 4 -- 5 -- 1...) lets say switch 1 has the backhaul link for the main Internet. Switches 3-4 is the loop part which we'd like to disable data between them unless the loop breaks somewhere else. In an outage (the BH link on switch 5 -- 1 dies for instance) then the loop between 3-4 is opened up and data from switch 5 now goes down the line to 4,3,2,1 and no one is the wiser.

I've tried setting rstp etc but never seemed to work, it would always cause a L2 bottleneck and crash the whole network it seemed. We aren't looking at going down a routed network just yet as all the sites are solar powered and power/number of devices are limited...

I've looked online for a while for a simple How-To for creating ring networks like this but have found nothing :( Please can we create such a document and share it for all users of Netonix switches as I think it will be good to understand.

Thanks heaps!

[mike99]

RSTP should be as simple as enable it glabally (top left of the STP tab) and enable it of every ports of your ring (don't enable it on port with AP where customer connect to).

Also put a lower priority (top right of the STP tab) on the switch at the edge of your network so the switch 1.

[sirhc]

We follow the 802 standard so RSTP works the same on our switch as any switch that offers RSTP.

All switches follow the standard for interoperability.

https://en.wikipedia.org/wiki/Spanning_Tree_Protocol


When I first started playing with RSTP I set up 3 switches in my LAB and played with the differnt values such as Priority, Priority per port, and Path Cost per port.

This allowed me to more understand what each value did and how I could get a specific link between the 3 switches to be in blocking mode by default and switch to forwarding when I unplugged a cable between the switches and then watched it switch back to blocking when I plugged the cable back in.

Nothing beats a LAB setup and spending an hour or so playing.

Setup 3 switches (you could use 2 but 3 is better).
Assign 3 differnt IPs in your subnet to each switch.
Log into the UI of each switch so you can see the RSTP Status on each switch and the effect when unplugging and plugging cables in.

[timb0]

OK, thanks, this makes sense for the most part, I have 3 different switches I can play with in a lab. I will do this over the coming days.

Regarding priority - what should I use? Switch 3 and 4 has the redundant link. a lower priority on switch 1? I don't understand how the priority works across different parts of the ring, is there some information I can read about it?

Cheers,

Tim

[mike99]

Lower priority = higher chance to become the root switch and, in STP, all traffic find the path with less cost up to the root switch.

Read section 1 (root bridge):
https://www.networkworld.com/article/22 ... takes.html

Cisco et Juniper have great doc about network stuff:
https://www.certificationkits.com/cisco ... ked-ports/