Hello all,
I have a network setup as illustrated in the attached diagram, which is actually an "internal LAN" for a system consisting of two physical chains. The two chains are linked via fiber optics on the mini-GBIC ports of the 4 x 2810-24G switches.
For the sake of my question, please assume that all the indicated links are required for redundancy purposes, and I cannot change the physical setup in a way that loses redundancy.
My problem is finding the optimal spanning tree configuration for the 2810-24G switches that will lead to a minimal reconfiguration time for the internal network in case of failure of either of the switches.
The software application running on the nodes 1-10 cannot cope with a long outage of the internal LAN.
I am looking at getting the observable outage, e.g. in terms of UDP echo requests not getting through, to as little as possible.
So first, I would like to ask the experts what is possible. Under 1 second? Under 3 s?
Secondly, how do I get there... let me tell you where I am.
I have disabled admin-edge and auto-edge on the interfaces between the switches, i.e. where the "patch cables" are connecting the switches inside a chain, and on the fiber trunks.
LACP is active on the fibers and on the patch connections.
RSTP has been forced via the CLI on all switches.
point-to-point mac has been forced on all the switch-to-switch interfaces.
Hello time has been set to 1 second.
loop-protect is disabled everywhere, and admin-edge + BPDU protection is set on all the ports leading to the nodes (non-switch-to-switch ports).
Additionally, I have
spanning-tree config-name "INTERNAL_LAN"
spanning-tree config-revision 1
and
vlan 1
name "DEFAULT_VLAN"
untagged 1-24
ip address 192.168.7.40 255.255.255.0
and
no stack auto-join
All switches are on default STP priority (32768) as a matter of choice, to ease things for future maintenance operations.
I am finding the interruptions when I power off the root switch too long for my liking.
I will provide more detailed outage statistics in a follow-up to this, but for the moment, does anyone have suggestions for some obvious performance tuning to RSTP that I might have overlooked, or anything I am doing wrong?
Thanks in advance,
Michael
#RSTP#Spanningtree#recovery#convergence#2810