WAP and Hot Spare Failover configuration

[MerakiJockey505]

We have several Family Health Center sites that utilize wireless connections for COW's (Computers on Wheels) as well as mobile and telehealth providers.  The sites are fairly large and require the use of usually 15+ WAPs.  Our best practice is usually to stagger the WAPs numerically throughout the clinic attaching even numbered WAPs to one switch and odd numbered WAPs to another.  The switches, sometime stacked and sometimes not, are then wired to a Meraki MX device with a hot spare as well as separate UPS backup batteries on twist lock plugs wired to separate J-boxes.  In sites utilizing MX65's or Higher we also try to utilize 2 types of Internet circuits such as a standard and a cradlepoint device or USB modem.  We consider this a pretty solid fail-safe to keep the Wireless connectivity active in the event of an MX or MS loss or drop.  When possible, we also keep access to a backup generator or long life battery system.  In the event of a loss or downed device, the WAPs are pretty good about going into repeater mode and filling the coverage spots.  Sometimes however, load balancing becomes and issue without a reboot of the active WAPs.  Does anyone have any alternative suggestions for keeping a balanced staggered configuration in the event of a fail-over?

[ChrisR]

   Well I think that typically this type of scenario really relies on a good RRM althorithm to help balance these off areas in a time of failure. For instance if you Odd AP switch goes offline leaving the Evens online the idea would be for the surrounding Even APs to bump up power to help fill in the gaps. Depending on spacing this may or may not cover everything.

   Unfortunately I have not seen as much consistancy on the Meraki RRM as say the Cisco side. With that said, it is much more improved over where it was a few years back, but still needs to have some improvements to work more reliably for this kind of thing.

 How are your devices designed to connect? Are they connecting on either 2.4 or 5Ghz bands or do you have it designed to operate on the 5Ghz band only? If you had it setup to the 5Ghz band only you could deploy either 40Mhz wide channels or even 20Mhz wide channels (if necessary, depending on channel overlap) and you could hardset the channels and powers on your APs. You could set the powers to provide the necessary overlap that you are looking for in this manor so if a switch is lost the power will already be there. This of course would take a bit of testing and tweaking to optimize it for your situation, but it maybe one way to ensure the redundancy that you are trying to design for.

  I realize hardsetting those channels and powers, might not sound appealing initially, but in some circumstances it can still be the way to go when trying to hit certain objectives such as yours.

Good Luck,

Chris

[MerakiJockey505]

Thanks @ChrisR, that's great  advice!  We have a test network set up with similar equipment and configuration.  I will definitely give the hard set channel frequency a try.   I wonder if the same could be said for the outdoor and "stadium" style WAPs?

[ChrisR]

Yeah this is something that could be applied in the same way on those APs as well. That is actually something that you see done in some of those scenarios... depending on the layout and situation. A combination of directed antenna focus and set power settings. I think there are a lot of methods in large venue type environments... as usual with wireless it is going to vary from one thing to the next.

[DarkStar]

@Chris

Great information on how to improve failed coverage. I really don't like the idea of manual settings. With a very small IT staff this defeats the purpose of buying Meraki with the set it and forget it sales pitch. Then there is the change log nightmare.

[ChrisR]

@DarkStar

 Yeah I would not suggest that to be done on every deployment, and in most I let RRM handle things unless I feel like it is not balancing well enough or if it is something like a warehouse that I designed in a specific way with specific power settings and antenna arrays. 

  In this case, what they were wanting to accomplish lent itself to be a more specific setup and possible solution. It is something to suggest trying for what they were trying to do, but not something necessary in a lot of situations.

Good Luck,

Chris