Core Implementation

[KirkM]

I have a random question...a question I must solve shortly!

If you have an existing network and you purchase, say a couple of 355-48X2's and you want to implement that new Meraki Stack as the NEW CORE....how might one go about that...somewhat easily?

A couple things to consider:

1. These are cloud devices so they must have internet access to be managed (of course you all knew that)
2. In this organization, the only internet available is on the SAME network as the core I'm trying to replace...so, it is effectively impossible to configure a "new" core on the same core.

Thoughts?  I considered building a completely separate VLAN, adding some routing so that VLAN can hit the internet and then performing the tasks...I'm just trying to make it as seamless as possible without building out a bunch of stuff that I'm going to have to undo.

Was just wondering if anyone out there had any ideas that they employed in a similar situation.  Thanks!

[DarrenOC · Accepted solution]

Hi @KirkM , our approach would be to configure the Meraki device management vlan on your firewall. Patch your new Meraki devices into them and let them register out.

Assuming to have all your VLANs and IP sublets documented. During an outage Window disconnect your existing core off the network. Replace with new core. Configure VLANs, IP subnets and switchport configs.

[KirkM]

Thanks for the reply...

Yeah, I'd considered the whole firewall option....that might be overkill if I'm just going to "note" the network configuration and then take everything down, bring up the new Core, then manually configure the whole enchilada on the fly.  Probably going to be the best bet anyway.

Now, if I can just get the Management IP to actually accept the static address instead of this "weird" thing I'm seeing now.  Thanks!

[DarrenOC]

Hi @KirkM , what weird issue are you seeing?

[KirkM]

The oddest thing.  I set the management interface to be static, I.E:

VLAN99

192.168.99.40

255.255.255.0

192.168.99.1

When I go to access it it still shows the IP address as the DHCP address 10.10.X.X the VLAN as 99 and it still works.  Strange.....I'm trying to just isolate the Stack on the Management VLAN for the moment just to fiddle but it's not letting me.  When I change the port, the stack is connected, to an ACCESS port VLAN 99 I lose the device.  Just odd.

I am upgrading the Firmware to 12.28 at the moment to see if this helps.

[Malco-Mike]

Just a heads up. I had updated our MS350-48's to the 12.28 firmware this last weekend and started having intermittent issues on Tuesday and then today my network basically went down. Network was hit and miss, tried pinging multiple websites and had a 50% drop rate. Getting onto Meraki site sometimes would connect. Ended up connecting to Meraki with LTE device and rolled back the firmware and that fixed the issues. Hopefully you don't have the same problem wit the 355's.

[KirkM]

Thanks for the heads up!  Thankfully nothing is plugged into these things yet.  They are brand new as of yesterday.  I may just roll them back, right now, to be safe.  Much appreciated.

[DarrenOC]

Hi @KirkM , are you setting the mgmt IP via the mgmt port or via the dashboard?  We’ve had some funnies in the past where setting via the dashboard the settings would take effect.

[KirkM]

I AM setting it via the Dashboard.  Let me patch in on the Management port and take a look.  Interesting.....Hmmmmmm

Thanks for the tip!

[DarrenOC]

Let us know how you get on.

[Claes_Karlsson]

I would have prepared the switch portconfig as a duplicate of your existing core, but with a different management address. Then connecting the new core to the old core with L2 cables. Depending if you have L3 SVI's or routing on the old core, i would then have moved one subnet each. Now your "downtime" will only be in short scenarios, the first when you move your L2 physical cables from the old core to the new core, then the second break will come when you move your L3 SVI's and routing for each subnet. It's important to make sure you have your STP configuration in place and make sure you don't get any blocking ports where you don't want them.

I prefer this kind of method rather than a forklift upgrade where you're doing a big bang and just replacing the whole stacks. 

[KirkM]

Claes, I'm with you!  I would have loved to do this!

Unfortunately, we are dealing with an ANCIENT core set of switches (old Dell 6224's in L3 SVI).  Have you ever had to deal with their Trunk vs. General switchport designation?  It's a nightmare!  Trunks work in some cases and General ports in others...and it's RANDOM!  Nightmare!!!

Sadly, in my case, it's going to have to be that forklift.  I've tried making minor changes and STP goes berserk.  I have to force an election and it's just a "mess sandwich" all over the place. lol

Appreciate the feedback though!