cloud server after docker is installed successfully, enter the start command:

sudo service docker start

system threw an exception: Failed to add /run/systemd/ask-password to directory watch: No space left on device

check the server space usage and find that it is not a server space problem. Upon examination, it was found that the following method could be used:

for immediate effect: add monitoring space

on the command line

sudo -i
echo 1048576 > /proc/sys/fs/inotify/max_user_watches
exit

or you can modify the configuration file to make monitoring long term:

sudo vim /etc/sysctl.conf

and then add:

to the end of the file

fs.inotify.max_user_watches=1048576

save and exit, and then enter the start docker command.