Sometimes x2go works fine. Other times I can't get the session back and logs look like this. server version 4.0.1.20. Same results occur when connecting from my Windows or Linux client.
$ uname -a Linux hercules 3.10.0-514.26.2.el7.x86_64 #1 SMP Tue Jul 4 15:04:05 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
==> messages <== Nov 18 02:00:32 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully
==> secure <== Nov 18 02:00:35 hercules sshd[33053]: Accepted password for andrew from 104.133.2.65 port 42971 ssh2
==> messages <== Nov 18 02:00:35 hercules systemd-logind: New session 13589 of user andrew. Nov 18 02:00:35 hercules systemd: Started Session 13589 of user andrew. Nov 18 02:00:35 hercules systemd: Starting Session 13589 of user andrew.
==> secure <== Nov 18 02:00:35 hercules sshd[33053]: pam_unix(sshd:session): session opened for user andrew by (uid=0)
==> messages <== Nov 18 02:00:41 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:00:44 hercules su: (to andrew) root on none Nov 18 02:00:44 hercules systemd: Started Session c387 of user andrew. Nov 18 02:00:44 hercules systemd: Starting Session c387 of user andrew.
==> secure <== Nov 18 02:00:44 hercules su: pam_unix(su:session): session opened for user andrew by (uid=0) Nov 18 02:00:44 hercules su: pam_unix(su:session): session closed for user andrew
==> messages <== Nov 18 02:00:44 hercules su: (to andrew) root on none Nov 18 02:00:44 hercules systemd: Started Session c388 of user andrew. Nov 18 02:00:44 hercules systemd: Starting Session c388 of user andrew.
==> secure <== Nov 18 02:00:44 hercules su: pam_unix(su:session): session opened for user andrew by (uid=0)
==> messages <== Nov 18 02:00:45 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:00:46 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully
==> secure <== Nov 18 02:00:47 hercules su: pam_unix(su:session): session closed for user andrew
==> messages <== Nov 18 02:00:50 hercules /usr/sbin/x2gocleansessions[3217]: andrew-51-1508260775_stDMATE_dp32: session status S desynchronized with current status (R) and session suspend already tried unsuccessfully Nov 18 02:00:50 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:00:54 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:01:00 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:01:01 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:01:01 hercules systemd: Created slice user-0.slice. Nov 18 02:01:01 hercules systemd: Starting user-0.slice. Nov 18 02:01:01 hercules systemd: Started Session 13590 of user root. Nov 18 02:01:01 hercules systemd: Starting Session 13590 of user root. Nov 18 02:01:01 hercules systemd: Removed slice user-0.slice. Nov 18 02:01:01 hercules systemd: Stopping user-0.slice. Nov 18 02:01:03 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully Nov 18 02:01:07 hercules /usr/bin/x2gosuspend-session: session with ID andrew-51-1508260775_stDMATE_dp32 has been suspended successfully