MS125 HA deployment

[ludwigbery]

Hi,

would it be possible to deploy MS125 as an HA pair? Also, does Link Aggregation is possible with Meraki Switches? cant find it in documentation. Hoping someone can shed some light.

thanks!

[jdsilva · Accepted solution]

When I think HA I generally thing about L3 devices. The MS125 is L2 only, so it's not capable of any HA functions. It also does not support physical stacking. 

It can do LACP based link aggregation. 

https://meraki.cisco.com/lib/pdf/meraki_datasheet_ms125.pdf

[PhilipDAth]

>When I think HA I generally thing about L3 devices.

I think there is wider scope than this with layer 2.  Such as having a stacked pair of switches and being able to dual connect the remaining access switches using LACP or being able to dual connect servers/storage to the network core using LACP.

This can all be done at layer 2.

If you adopt this thinking then you really need a minimum of MS210's stacked together.  If you give up on LACP and channeling, and whatever that needs to be dual connected can handle the failover itself, then you could use a simple pair of MS125s connected together - otherwise, yep, you need a minimum of MS210's.

If you want redundant power then you need to step up to MS250s.

[cmr]

@PhilipDAthI'm pretty sure we are using Cisco RPS2300 redundant power systems on our MS225s and MS210s though it's been a busy week so I might be mistaken!

[PhilipDAth]

That's true - but they have quite a few limitations.

For example, they can only offer redundant power for two failed power supplies.  So you can plug in a stack of 4 switches, but only 2 of them can use it concurrently (this is assuming you load the RPS2300 up with two power supplies otherwise you are only covered for a single power supply failure).

Also you can't use them to provide "A" and "B" power.  If the "A" power rail goes down, all the switches will power down except two (or one if you only have a single power supply in the RPS2300).

Also if I recall correctly, they only cover the core switch operating power and not PoE.  I could be wrong.  So the switch will stay up but phones, APs, etc will go down.

I've had a problem getting the switches to fail back from the RPS2300 to mains power before as well requiring the switches to be power cycled.

I'll be blunt.  I don't like them.  I don't tell my customers that they exist.  I think they are pretty expensive as well.

[cmr]

LOL, you have them pretty much bang on!

We had them left over from the old 3560s that the MSs replaced.  We do only use them to protect stacks of 2 switches and I've yet to test the PoE when on RPS.  With the 3560s they previously powered, the PoE did work (we have 750W/1100W PSUs in them) and did switch back okay, but with older (2960) switches that used the smaller connector, they were all but useless...

[PhilipDAth]

The other thing with the RPS2300 - in the Cisco entrerprise world you had to upgrade the RPS2300 via the switch, and any advanced options (like load priority) had to be configured via the switch.

I wonder when connected by a Meraki switch if the RPS2300 ever gets its firmware updated, or are you stuck with whatever firmware it ships with.  And as for configuring things like load priority - you are out of luck in the Meraki world.

[cmr]

It is a big dumb box once there are no 3000 series Cisco switches connected...   The MS doesn't even tell you it is connected in the GUI!

[jdsilva]

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@PhilipDAth wrote:

>When I think HA I generally thing about L3 devices.

I think there is wider scope than this with layer 2.  Such as having a stacked pair of switches and being able to dual connect the remaining access switches using LACP or being able to dual connect servers/storage to the network core using LACP.

This can all be done at layer 2.

---

Yeh this was why I qualified my response. I thought the OP may not have the same view as me. I suspected that Stacking was the real ask, but it's possible that VRRP may have been desired too. 

[ludwigbery]

Hi @jdsilva , @PhilipDAth , @cmr 

thank you for the discussion and references.

Hope you can further help me with my final concern, would the uplink ports on MS125 can be used as trunk? can we pass multiple VLAN on each? 

I'm planning to connect servers carrying multiple Virtual Machine & VLANs.

[PhilipDAth]

>Hope you can further help me with my final concern, would the uplink ports on MS125 can be used as trunk? can we pass multiple VLAN on each? 

Yes.