MX84 IPv6 woes

[BHC_RESORTS]

Has anyone had any success with IPv6 and the MX84? We have been trying to deploy since January and have an open case with support that we can't get any response on.

We are using spectrum (legacy charter) fiber. They assign us a /127. Basically like a /30 point to point in ipv4. One end of the /127 is their CiscoME, the other is our mx. We then have a /48 routed to us that we can break up in to /64s however we please.

The MX will show the assigned /127 as being up, but will not route traffic. Spectrum support says their end is working fine, and pcaps seem to support this.

This is delaying our IPv6 deployment as we are testing it inhouse before deploying company wide.

Suggestions??

[cmr]

@BHC_RESORTS yes, working no problem, but we get a /56 from each ISP.  Apologies, I have seen how much you have been trying, but I just don't think Meraki support that addressing model (hopefully) yet.

[BHC_RESORTS]

@cmr Entirely possible that's the case. But if so, we'd rather they just come out and tell us "it won't work yet" instead of having a ticket open for 3 months now, and not replying to us when we ask for an update on the status.

We even reached out to our rep, who told us they were no longer our rep, and that the issue would be passed along to the appropriate party. That was only 2-3 weeks ago.

Not a good look when our very expensive renewal and product refresh is coming up in 2024...we're talking a 7 figure number here.

[AlexP]

How is the /48 being given to you? I ask because it must be advertised via DHCPv6-PD for us to be able to use it.

[BHC_RESORTS]

I'll have to check. However we can't even get the /127 on the MX to respond. The "gateway" of the /127 which is Spectrum's on prem router, pings and traces just fine. The only other IP in the /127, which is what we have assigned to the MX, doesn't ping. The MX shows the IP addresses green and online.

According to Spectrum:

Looks we are not receiving any Router advertising from your service, claiming the IPv6 address.

Captured traffic shows that we are getting the client's solicitation, where they are asking for our IP address.

Our device is responding to them with a Router Advertisement.

Our device is sending out Solicitations asking for the client IP.

We are not receiving any Router advertisement from the client, claiming the IPv6 address.

[AlexP]

It sounds like we're dealing with two separate issues here then.

Regarding the /127 issue, it sounds to me like they're claiming they're sending us a neighbor solicit - how you do the L2 to L3 mapping process in IPv6 that was performed by ARP in IPv4 -  and we're not responding, but we'd need more clarification on that, and a .pcap would also be highly recommended if you haven't taken one already, since we'll want to be able to see what's going on on the wire here.

[BHC_RESORTS]

@AlexP we gave pcaps initially in the trouble ticket, and I just took one as well.

[AlexP]

I'd be curious to know what they said when you shared those results with them, because, at a glance at least, we are responding as we should be.

[BHC_RESORTS]

I'll follow up with Spectrum on that and see what they say. This thread has been much more constructive so far than my support ticket, so I'm very appreciative!

Are there any behind the scenes logs that may or may not show what the MX is doing when I turn on the IPV6? It "thinks" it is connected as it shows the assigned /127 being green, but I'm not sure what logic it uses to determine that.