Failed to restore all the required visuals. - Can't resume the NX session on this display.

[mikedep333]

As mention in X2Go bug 891 and VcXsrv (X2Go/Arctica Builds) Issue 4, the following causes a session to fail to resume:

1. Start the nxagent session from a client (nxproxy) whose X server supports StaticColor Visual Types (For example, VcXsrv 1.17.0.0-2 with -multiwindow as the only argument, assuming the Windows OS has WGL (Windows OpenGL) support. Nvidia, AMD & Intel drivers all provide WGL.)
2. Suspend the session.
3. Attempt to resume the session on a client whose a X server does not support StaticColor Visual Types. (For example, that same VcXsrv machine over RDP, or Ubuntu 14.04's Xorg server.)

The errror that nxproxy produces after step 3 is:

Failed to restore all the required visuals.
Can't resume the NX session on this display.

I will probably modify VcXsrv (X2Go/Arctica) builds to no longer support StaticColor. But it would be nice if we could disable StaticColor in nxagent too (perhaps via an argument.) And if we could make a session resume despite running into this situation, that would be even better.

Note that with VcXsrv 1.17.0.0-2, the following StaticColor visual types are available:

0x211
0x212
0x213
0x214

And if you run xdpyinfo against an nxagent 3.5.0.31 started from nxproxy 3.5.0.31 running on VcXsrv 1.17.0.0-2, you'll see that it supports 1 StaticColor type:

0xa6

[sunweaver]

@mikedep333: Do you have any recipe that allows me reproducing this issue on Linux-only setups?

[uli42]

We have the tolerancecheck setting but unfortunately it does not cover visuals.