The default Duplicati architecture for both service and non-service is a parent process that runs from the installation (e.g. C:\Program Files\Duplicati 2), looks for installed updates, and starts the latest as a child.
Activate button exits the child with an MAGIC_EXIT_CODE that gets parent to restart on the newer install.
root 22860 1 0 07:09 ? 00:00:00 DuplicatiServer /usr/lib/duplicati/Duplicati.Server.exe
root 22864 22860 2 07:09 ? 00:00:31 /usr/bin/mono-sgen /usr/lib/duplicati/Duplicati.Server.exe
# strace -p 22860 -p 22864 -o /tmp/strace.activate.log -tt -f
22864 07:36:02.791955 exit_group(126) = ?
22864 07:36:02.812334 +++ exited with 126 +++
22860 07:36:02.812473 <... futex resumed> ) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
22860 07:36:02.812541 --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=22864, si_uid=0, si_status=126, si_utime=2873, si_stime=214} ---
22860 07:36:02.812615 futex(0x55d9e89f7480, FUTEX_WAKE_PRIVATE, 1) = 1
22862 07:36:02.812722 <... futex resumed> ) = 0
22862 07:36:02.812798 wait4(22864, [{WIFEXITED(s) && WEXITSTATUS(s) == 126}], WNOHANG, NULL) = 22864
22860 07:36:02.812940 rt_sigreturn({mask=[]}) = 202
22860 07:36:02.813043 futex(0x55d9eaf5fc78, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NULL, 0xffffffff <unfinished ...>
22862 07:36:02.813105 futex(0x55d9eaf5fc78, FUTEX_WAKE_PRIVATE, 1) = 1
22860 07:36:02.813230 <... futex resumed> ) = 0
22862 07:36:02.813357 wait4(22863, 0x7fd9e9af7d50, WNOHANG, NULL) = -1 ECHILD (No child processes)
22862 07:36:02.813472 futex(0x55d9e89f7480, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, NULL, 0xffffffff <unfinished ...>
22860 07:36:02.814095 openat(AT_FDCWD, "/usr/share/Duplicati/updates", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 5
Good to hear. Thanks. In terms of availability, it’s “supposed” to be a small outage, then back up on new…
Non-Windows systems are basically paired Duplicati processes, plus something above, maybe systemd.
Windows systems have Duplicati.WindowsService.exe in the mix. A maximum view (and more) is at link:
[SOLVED] Is it ok that I see 5 processes of Duplicati in Windows Task manager?
In both Windows and Linux there’s OS administrator level control (services.msc, systemctl, etc. ) needed to totally take down the service, but there’s also the hopefully-short outage when Duplicati runs the update.