all 39 comments

[–]UncleSaltineLESS ANGRY AND HAS A NEW JOB 2 points3 points  (25 children)

Rapid-PVST is interoperable with RSTP. You should be fine as is.

Adjust your bridge priority on your Meraki and it should act as the root bridge

[–]jwwork[S] 0 points1 point  (23 children)

I have a 3750 trunked to an MS425. The 425 has priority 4096 and the 3750 is at default priority. On the trunk between them I allow vlan 2,210,and 211. This is the result when the 3750 is in rapid-pvst.

MerakiTrunkTest#sh spanning-tree root detail
  Root ID    Priority    32770
             Address     001d.e504.0c00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
  Root ID    Priority    32978
             Address     001d.e504.0c00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
  Root ID    Priority    32979
             Address     001d.e504.0c00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

[–]PE_Norris 0 points1 point  (22 children)

Can you output a sh span sum and a sh span vlan 210?

[–]jwwork[S] 0 points1 point  (21 children)

MerakiTrunkTest#sh span sum
Switch is in rapid-pvst mode
Root bridge for: VLAN0002, VLAN0210-VLAN0211
Extended system ID           is enabled
Portfast Default             is disabled
PortFast BPDU Guard Default  is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default            is disabled
EtherChannel misconfig guard is enabled
UplinkFast                   is disabled
BackboneFast                 is enabled but inactive in rapid-pvst mode
Configured Pathcost method used is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0002                     0         0        0          1          1
VLAN0210                     0         0        0          1          1
VLAN0211                     0         0        0          1          1
---------------------- -------- --------- -------- ---------- ----------
3 vlans                      0         0        0          3          3

MerakiTrunkTest#sh span vlan 210

  Spanning tree enabled protocol rstp
  Root ID    Priority    32978
             Address     001d.e504.0c00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32978  (priority 32768 sys-id-ext 210)
             Address     001d.e504.0c00
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  300 sec

Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po1                 Desg FWD 3         128.488  P2p

[–]PE_Norris 0 points1 point  (20 children)

I'm not a meraki guy, but are the vlans and spanning tree even defined on it? I assume the Po1 is towards the core. Since it's a different STP type, I'd expect to see P2P-peer.

Are you learning macs over it?

[–]jwwork[S] 0 points1 point  (19 children)

Yes the vlans are defined on the Meraki side. Po1 is the port channel going to the core. The only STP options on the Meraki are a choice between STP and RSTP and the ability to set the priority. I have it set for RSTP and priority 4096.

[–]itslateCCIE 0 points1 point  (4 children)

if your 3750 is winning root its either 2 issues:

the vlans arent allowed on the other side of the trunk, and therefore isolated

priority isnt configured right on the meraki

[–]WendoNZ 0 points1 point  (2 children)

I could be wrong here, but don't you need VLAN1 on that trunk to be able to pass the STP packets between the two switches? My understanding was when interfacing to RSTP all STP traffic happened on VLAN1

[–]itslateCCIE 0 points1 point  (1 child)

doesn't have to be vlan 1. as long as native vlan is configured correctly on both sides then there's a couple different scenarios

[–]jwwork[S] 0 points1 point  (0 children)

I am allowing all vlans on the Meraki side but I was not allowing vlan 1 (native) on the Cisco side. I just changed the Cisco side to allow all vlans. After that, vlan 1 shows the Meraki as root but all other vlans still show the 3750 as root.

[–]jwwork[S] 0 points1 point  (0 children)

The Meraki is allowing all vlans on the trunk and it's priority is set to 4096.

[–]PE_Norris 0 points1 point  (13 children)

Are you learning macs from the meraki side?

[–]jwwork[S] 0 points1 point  (12 children)

There are no clients connected to the 3750 but the MAC table on the Meraki side does show the MAC of the 3750.

[–]PE_Norris 0 points1 point  (11 children)

What about the 3750? Assign an svi to the meraki and see if you see it’s Mac on the Cisco

[–]jwwork[S] 0 points1 point  (10 children)

I see the mac address of the Meraki on the 3750 on vlan 1.

[–]asdlkfesteemed fruit-loop 5 points6 points  (2 children)

oh fucking god why would you replace your core with meraki.

Access switches, ok, sure...

Meraki are not core switches.

[–]sysvivalLord of the STPs 0 points1 point  (0 children)

Maybe his definition of "core" differs from yours.

Just saying.

[–]-lambtron- -2 points-1 points  (0 children)

They make good WAPs, that's about it.

[–]jasonlitka 3 points4 points  (2 children)

have to replace core switching with Meraki

Why? It sounds like it doesn't meet your needs.

[–]jwwork[S] 0 points1 point  (1 child)

I know of the issues, it's the organizations plan to replace all the switching with Meraki but the core has to come first due to some upcoming projects.

[–]jasonlitka 0 points1 point  (0 children)

To be clear, I like Meraki. I use their MX gateways and a bunch of their MR APs. I've got a couple MS switches but am not thrilled with those.

What I was saying was that the Meraki switches at the core, those switches by themselves, do not meet your needs assuming your post is accurate (and I don't have enough experience with the MS switches to say either way). You really need to talk to support about it, they're really good, and if it's accurate, go back to management and say that it's not a good idea to do JUST this replacement.

[–]jwwork[S] 0 points1 point  (0 children)

Here is the output of "show spanning-tree mst" after switching stp modes from rapid-pvst to mst on the 3750.

MerakiTrunkTest#sh spanning-tree mst 

##### MST0    vlans mapped:   1-4094
Bridge        address 001d.e504.0c00  priority      32768 (32768 sysid 0)
Root          address e055.3dd4.af28  priority      4096  (4096 sysid 0)
              port    Gi2/0/1         path cost     20000    
Regional Root this switch
Operational   hello time 2 , forward delay 15, max age 20, txholdcount 6 
Configured    hello time 2 , forward delay 15, max age 20, max hops    20

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi2/0/1          Root FWD 20000     128.55   P2p Bound(RSTP)

Meraki is connected to gi2/0/1.

[–]SuddenWeatherReportSmarty-pants 0 points1 point  (2 children)

avoid instance 0, use instance 0

Edit use instance 1

[–]jwwork[S] 0 points1 point  (1 child)

Seems like solid advice.

[–]SuddenWeatherReportSmarty-pants 0 points1 point  (0 children)

Haha I meant 1

[–]imatripandahalfCCNP -2 points-1 points  (3 children)

Meraki switches are slow AF, and support maybe 1/10 of the features of a real switch.

[–]asdlkfesteemed fruit-loop -1 points0 points  (2 children)

No way man. They support the exact same "on" or "off" feature that an electrical light switch supports!!!

What's your problem? why you hatin on meraki ?

but seriously, fuck meraki .

[–]imatripandahalfCCNP 1 point2 points  (1 child)

A Meraki MS350-48 is basically a glorified cloud managed Cisco Catalyst 3850 that has to be re-licensed every year. You don't pay the rent, it stops working. For a few bucks more on the outset, you can get an actual 3850 switch.

[–]Wendallw00f 1 point2 points  (0 children)

yeah but 3850's don't give you nice colours and pingy tests