FW 4.4.1 does not allow VPN traffic to Pass

We have hundreds of GX440 modems all on a zero-tunnel private nework (VZW), which all have a Digi WR41 connected to them. Using modem FW Version 4.3.6, our VPN tunnels operate fine with no known issues.

We purchased new GX440s recently which shipped with 4.4.1 FW installed. With no other changes but the modem, our VPN failed to establish thru this link. I downgraded the same modem to version 4.3.6 and it works fine. This is repeatable, as I tested this with multiple modems/Digi routers with the same results.

What has changed in FW 4.4.1 and later that causes a VPN link to fail to establish? Some new default setting? As it stands, we are unable to further upgrade our devices to the latest firmware until this is resolved.


Are the modems set to “Ethernet Uses Public IP” or in other words IP passthrough where the modem passes the IP address it receives from Verizon to the DIgi?

Yes, the modems are set to “Ethernet Uses Public IP”. The modem is passing it’s static address thru to a Digi WR41, which is where our endpoint equipment is connected. The Digi is also the device that hosts the VPN tunnel connection between our head end and the remote equipment. This configuration has been working flawlessly up until version 4.4.0/4.4.1.

Any ideas? Are there new IP rules that were instituted in 4.4.x versus 4.3.6?

Many thanks in advance!

Have you tried the 4.4.2 release that Sierra Wireless posted recently?

I have not, but I fully expect that it will exhibit the same issue, as it has traveled from 4.4.0 to 4.4.1. I can and will test this, but am not optimistic. I think I need to bring my reseller in on this.

UPDATE: With version installed, it appears to work. I will have to do further testing to ensure it’s reliability (as the previous 2 versions do not instill much confidence). Here’s hoping. Thank you for the suggestion to try it.