Controllerless Networks

I have a IAP-225 and a IAP-205.
The 225 is configured as a the controller and all working fine, I've added the 205 in and given it an IP and it seems to join the cluster fine.
Extended SSID is disabled on the 225.
I've then removed the network cable from the 205 and it then rejoins as a mesh member.

It works for about 5-10 minutes, takes clients, and I can ping it

It then disappears, all the lights remain normal....
Any ideas where to start with troubleshooting this?

hing honestly would be to start with TAC as you may end up there. You can check the AP console logs to see wht the AP is doing, why it's rebooting or dropping off. I would also check and make sure that the 205 is not wired to something that is giving it an IP address.

Just checking I've got the basics correct:

VLAN10 - Internal Clients
VLAN30 - Management VLAN

VLAN40 - Guest VLAN

On the 225 - I've configured a static IP and left the VLAN as 0.
On my switch this port is untagged as VLAN30 and tagged with 10 and 40.
I've set a VC IP and set the VLAN to 30.

I've setup the SSIDs, all is good, clients connected and working fine

On the 205 I've just set the static IP and set the VLAN as 0
I've left the VC address as 0.0.0.0, but changed the VLAN to 30.

Is that correct so far?

So this is going to be odd, and if you don't have easy access to the APs then I would work through TAC first to ensure what's being done won't orphan your APs. 

With mesh, even if your management VLAN is untagged, the APs need to be able to carry it if your uplink is not native on VLAN 1. However, the new GUI in 8.4 is missing this currently. So if you are running 8.4, you will need to switch to the old UI (top right, switch to old UI). From there, go to System (top right), then General tab, and click the 'show advanced options' (bottom left). There's an 'Uplink switch native VLAN' where you would enter '30' (or whatever the VLAN is where your IAP management is carried). 

You can find more information in the user guide, where to find it, etc. Just search for 'Uplink switch native VLAN'. You can try that, but since I'm not 100pct on your topology, if you don't have hands on access to the APs to roll the change out should it break, I would work through TAC. 

That's my CYA :)

I have access to the APs and this isn't a true production environment so I'm able to break things without too much of a problem ;)

I did already have the Uplink switch native VLAN set to 30 though (otherwise I couldn't reach the VC from my other PCs)

The VC IP address is confusing me slightly:

I set it as 172.16.30.153 and VLAN30 on my master AP. 
Do I set an VC address on the others APs in the cluster or should they be 0.0.0.0 and VLAN30?

This isn't directly related to my orginal question, but taking the opportunity to get my knowledge solid on a wired cluster before troubleshooting a mesh

Thanks for all your advice so far :)

VC IP is just another IP to advertise from the VC if you want to have a static IP defining the VC, and let all the APs just get DHCP. Without the VC IP, if the APs all change channel, you have to find the VC's IP and log in there.

Sorry to be dense here!

I understand that the access points themselves obviosuly have a IP on the Eth interface which is the devices actual IP. In my case thats

I understand the VC address is essentially a loopback on a given device

I assume the idea would be in a cluster that the VC address will always be available (like the management inferface of a decidate controller) and can float between which ever of the IAPs is the current master.

So if an AP that is the current controller leaves the cluster for some reason another device will 'take' that ip.

What I don't get is if I should set the the same VC address on each IAP, but the devices are smart enough for only one of them to be live at any one time, or if I should set the VC IP on only 1 IAP and the devices handle it themselves.

So basically in a situtation where there isn't DHCP involved do you set the VC address on every IAP, and what do you set it to?

I'm sure this is really simple stuff!

Ehen you log in to a VC, or more specifically if the VC is established and you try to log in to the GUI on *ANY* AP in the VC cluster, it will redirect you to the VC Master. So you don't need to enter it into each AP, just the VC master (which with the GUI redirect makes it hard to do it to each AP). Once configured on the VC Master, it will push the config to the rest of the APs as part of the config.

Got it - thanks for the explaination :)

I've given up with the mesh, and I've dropped a cable and all is now working perfectly.