Recent Firmware updates on R8000 and R7000 break SonicWall SSL VPN Connectivity

[phoenix13]

I have spent nearly 40 hours investigating connectivity issues with SonicWall SSL VPN using the Dell SonicWall NetExtender client and the Windows 10 SonicWall Mobile app, which resulted in the root cause being Netgear Firmware updates, so am posting here for the benefit of others and also in the hope that Netgear resolve the issue.

I have tested and verified the issue on Netgear R8000 X6 & Netgear R7000 devices, connecting to SonicWall SSL VPN devices in Palo Alto and London (waiting on firmware version from the respective IT teams), but our Atlanta and Manchester offices do not experience the issue and they are on older SonicWall firmware versions with the Dell icon, rather than the new SonicWall S in a shield icon.

I've tested both of these devices using PPPoE on FTTP connections using 2 PC's, 2 laptops and an Android mobile device and also excluding the Netgear router (conntecting the network cable directly to the PC's and Windows performing the PPPoE connectivity) to verify 100% that it's a Netgear firmware issue.

On the Netgear R8000 X6

The issue occurs from firmware version 1.0.3.48

The most recent version without the issue is 1.0.3.46

On the Netgear R7000

The issue occurs from firmware version 1.0.7.12 (also tested version 1.0.9.6)

The most recent version without the issue is 1.0.7.10

Netgear, please resolve this issue in newer firmwares, otherwise I suspect that more people will be affected by this in future.

[phoenix13 · Accepted solution]

@jlmartinjr, I did manage to get somewhere on this, I worked with Netgear to provide debug details that they used to develop a fix, which I successfully tested in a debug firmware build, but I'm not sure when this will be included in the mainstream firmware release.

I did find that I could reliably revert to R8000 firmware version 1.0.1.16 and was then able to connect to the SonicWall SSL VPN's, I would suggest that you try this in the short-term until the latest firmware resolves the issue.

[phoenix13]

Additional Information:

Both of the Palo Alto and London SonicWall Firewall/SSL VPN's being affected by this issue are running SonicOS Enhanced 6.2.6.1-25n

[jlmartinjr]

did you ever get anywhere with this,  I have updated to the latest firmware and I am having no luck.

Mine is a x6 R8000

[phoenix13 · Accepted solution]

@jlmartinjr, I did manage to get somewhere on this, I worked with Netgear to provide debug details that they used to develop a fix, which I successfully tested in a debug firmware build, but I'm not sure when this will be included in the mainstream firmware release.

I did find that I could reliably revert to R8000 firmware version 1.0.1.16 and was then able to connect to the SonicWall SSL VPN's, I would suggest that you try this in the short-term until the latest firmware resolves the issue.