Daemon stop to wait for socket activation


#1

Hello there.

I have a trouble.
A few days ago, snapd has stopped running after upgrading.
Current version is snapd/2.37.4ubuntu0.1.
OS is utbuntu16.
The result of the status command is as follows.

Apr 04 21:46:54 ip-10-2-1-73 systemd[1]: Starting Snappy daemon...
Apr 04 21:46:54 ip-10-2-1-73 snapd[1925]: AppArmor status: apparmor is enabled and all features are available
Apr 04 21:46:54 ip-10-2-1-73 snapd[1925]: daemon.go:379: started snapd/2.37.4ubuntu0.1 (series 16; classic) ubuntu/16.04 (amd64) linux/4.4.0-1079-aws.
Apr 04 21:46:54 ip-10-2-1-73 systemd[1]: Started Snappy daemon.
Apr 04 21:46:59 ip-10-2-1-73 snapd[1925]: daemon.go:611: gracefully waiting for running hooks
Apr 04 21:46:59 ip-10-2-1-73 snapd[1925]: daemon.go:613: done waiting for running hooks
Apr 04 21:46:59 ip-10-2-1-73 snapd[1925]: daemon stop requested to wait for socket activation

If you know the cause or have some ideas, could you tell me that?
Best regards.