Pings to and from vMX failing

[stgonzo]

Hello,

I recently deployed a second vMX in Azure which uses BGP for routing for HA.  Everything is working fine from a user’s point of view, we have disabled one vMX at a time , and user traffic is working fine over both vMX appliances, the only issue is we can’t ping the second vMX appliance for monitoring purposes.  The original vMX doesn’t have the same issue, vMX2 is using some of the same azure resources and others are copied.

Ping tests

vMX2 to any hub or spoke site MX fails

Any hub or spoke site MX to vMX2 succeeds.

vMX2 to a device in a hub or spoke site fails

A device in a hub or spoke site to vMX2 fails

vMX2 to 8.8.8.8 succeeds

A packet capture on vMX2 when pinging from a device in a hub site, shows vMX2 receiving the request and then responding to it, but the reply doesn’t make it back to the hub vMX2.

A packet capture on a device in a hub site when ping from vMX2 shows ping requests from and ping replies to vMX2, but they do not reach back to vMX2

Any ideas?

I have an open support ticket for this issue.

[PhilipDAth]

Check the type of public IP assigned to each VMX (is it a "basic" or "standard" sku IP address).

Also check they are both in the same mode (such as VPN concentrator mode).

[stgonzo · Accepted solution]

This is quite an old post but the issue is now resolved.

The pings started working suddenly with no changes mades, but after 2-3 months the pings failed again.  The solution was to advertise the IP address of the vMX from the VPN page, had no issues for 4/5 months now