Meraki MX68 - WAN DHCP - release IP?

[James_S]

We use Merkai MX devices for trials that take place all over the country.

we will configure an MX, switches, APs, etc in our home office, fully test, then ship the "Trial Kits" to hotels, offices, short term rentals, etc.

When we configure the kits the MX68 obtains a WAN IP through DHCP and all works fine.

we configure everything and ship.

then, when it arrives on site it doesn't 'work'.

It appears that the MX68 is holding on to the DHCP from our main office. 

so far having the onsite tech do a factory reset on the router is the only way i know of to make it work.

is there a better way?

do i need to update my runbooks to include a factory reset on-site and start shipping with a paperclip?

thanks for your input

[PaulMcG]

That's kind of an odd behavior, I've done the same thing with MX devices with DHCP for the WAN port and moved from site to site with no issues.  Depending on the model of MX you are using, you could always use WAN2 in your office and then WAN1 when on site.  But it shouldn't behave in the way you describe.

[Ryan_Miles]

I too have not seen this and would not expect it. The MX when powered up should use DHCP on any connected WAN port (unless a static was set).

Is the provider equipment being powered on at the same time as the MX? I've seen plenty of modems that learn the first connected MAC address. So, if the MX is connected to the modem and something else was previously connected it won't hand out an IP without a reboot of the modem.

[James_S]

it's hard for me to tell what's exactly happening because i'm not on site.

I've had 2 events in the last 6 months where i had to do a factory reset on the MX68 to get connectivity.

Yesterday when it happened the device was in a weird state and said DNS was invalid. 

when i accessed the DHCP page I saw that it was my home office IP address and DNS information instead of the hotel.

we were using 10.x.x network and they are using 172.x.x

i'm not even sure how it came online at all. it's really hard to troubleshoot when i don't have any knowledge of the hotels network, etc.

i'm assuming it's something with DHCP since the invalid information was still being displayed on the web GUI.

[PaulMcG]

If the devices come online and giving a DNS error, just give it time and the warning will go away.  If you really it gone sooner, you could send a reboot command, but if the device shows as connected but with an error, it's still functionnal, the error is more informative than anything.

[James_S]

we tried rebooting when we had the DNS error and we lost connectivity. 

i believe there is a combination of things going on.

maybe mac authentication at the local site or some type of other issue stopping DHCP from working.

that issue gets resolved, but at that point the Meraki has been up for a while and doesn't try to get new DHCP?

maybe waiting for some type of timeout?

i let it go for about 4 hours yesterday before performing the factory reset.

after on-site support did reset it came right up.

[Aaron_Wilson]

Like others said, the reported IP and DNS errors can be delayed in updating.

If you are at a site that mac filters, always have them enter the mac (don't forget to provide the offset mac) before booting it. But I try to always ask for an open non-captive portal connection.

And yes, I have seen the WAN interfaces timeout on DHCP.

The best is when the property gives a connection that allows 80/443, but nothing else. That's a real treat to diagnose because the dashboard gives all kinds of weird info. Only after you connect a PC to the port and try something like SSH does it become apparent what the issue is.

[PaulMcG]

Yeah like you said sounds like a combination of things.  I've seen some ISP modems have the sticky MAC problem as well.  Any time I have an install with an ISP I know that can be an issue I reboot the modem at the same time I have the MX connected.  

You could make rebooting the ISP modem part of the setup process for a few sites and see if that solves the problem.  But taping a paperclip to the box is a good backup.