e9b9f33aee
There is a race upon reload, where it can happen that: 1. systemd forks off /bin/kill -HUP $MAINPID 2. Current instance forks off new one and notifies systemd with the new MAINPID. 3. systemd sets new MAINPID. 4. systemd receives SIGCHLD for the kill process (which is the current control process for the service) and reads the PID of the old instance from the PID file, resetting MAINPID to the PID of the old instance. 5. Old instance exits. 6. systemd receives SIGCHLD for the old instance, reads the PID of the old instance from the PID file once more. systemd sees that the MAINPID matches the child PID and considers the service exited. 7. systemd receivese notification from the new PID and is confused. The service won't get active, because the notification wasn't handled. To fix it, update the PID file before sending the MAINPID notification, similar to what a comment in systemd's src/core/service.c suggests: > /* Forking services may occasionally move to a new PID. > * As long as they update the PID file before exiting the old > * PID, they're fine. */ but for our Type=notify "before sending the notification" rather than "before exiting", because otherwise, the mix-up in 4. could still happen (although it might not actually be problematic without the mix-up in 6., it still seems better to avoid). Signed-off-by: Fabian Ebner <f.ebner@proxmox.com> |
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| .. | ||
| acme | ||
| api2 | ||
| backup | ||
| bin | ||
| config | ||
| server | ||
| tape | ||
| tools | ||
| auth_helpers.rs | ||
| auth.rs | ||
| client_helpers.rs | ||
| lib.rs | ||
| rrd_cache.rs | ||
| traffic_control_cache.rs | ||