Applicable to:
- Plesk for Linux
Symptoms
-
Webmail is not accessible:
CONFIG_TEXT: 500 Internal Server Error
-
Mailboxes may not be accessible and the following error is shown in the
/var/log/maillog
file:CONFIG_TEXT: mail16 dovecot: service=imap, user=johndoe@example.com, ip=[203.0.113.2]. Warning: Inotify instance limit for user (UID popuser) exceeded, disabling. Increase /proc/sys/fs/inotify/max_user_instances
-
Repairing web configuration finishes with error:
# plesk repair web
Repairing server-wide configuration parameters for web servers .. ERR [util_exec] proc_close() failed ['/usr/local/psa/admin/bin/httpdmng' '--reconfigure-server'] with exit code [1]
[FAILED]
- httpdmng failed: ERR [util_exec]
proc_close() failed ['/usr/local/psa/admin/bin/nginx_control' '--restart'] with exit code [1]
Can not reload proxy server:
Updating the file of sharing passwords and permissions of users -
Apache restart finishes successfully, but the following notification is shown:
# service httpd restart
Redirecting to /bin/systemctl restart httpd.service
Error: No space left on device -
There is sufficient disk space and inodes on the server, what can be checked by executing the commands below:
# df -h
OR
# df -i
-
OSSEC IDS is installed on the server.
-
Apache restart fails:
# service apache2 restart
Failed to add /run/systemd/ask-password to directory watch: inotify watch limit reached
Cause
Inotify subsystem limits are exceeded. Possibly, by the intrusion detection system.
Resolution
Note: if you do not have a root access to Plesk via SSH, contact your hosting provider regarding the issue.
-
Login to Plesk server via SSH
-
Increase limit for
fs.inotify.max_user_watches
andfs.inotify.max_user_instances
kernel parameters in the/etc/sysctl.conf
file:Note: if Plesk runs on virtual container, the kernel parameter should be increased on hardware node
CONFIG_TEXT: fs.inotify.max_user_watches = 560144
fs.inotify.max_user_instances = 512 -
Apply the changes:
# sysctl -p
Comments
5 comments
Could this not be fixed by using Dovecot as MDA (Mail Delivery Agent) for Postfix?
https://workaround.org/ispmail/jessie/postfix-dovecot
@Stéphan Schamp
The root cause of the issue is not an MDA related, but an OS related one, so using Dovecot is not a workaround for it.
@Alisa Kasyanova
I was thinking about not having to deal with inotify watchers in the first place, as I believe dovecot now is using inotfy watchers to monitor the inboxes for new mails (dropped there by Postfix).
But Postfix can tell Dovecot (over unix sockets) that there is a new mail, which is a much more logical approach.
Thus removing the need for these inotify watchers.
Hello @Stéphan Schamp,
My apologies for the late response.
The support request was created to check this suggestion deeper.
Hello @Stéphan,
Yes, LMTP can avoid this issue, but LDA is much easier to be implemented with Postfix and Qmail.
I have created a request on uservoice to consider replacement Dovecot LDA with Dovecot LMTP.
Please vote for this feature at https://plesk.uservoice.com/forums/184549-feature-suggestions/suggestions/36135496-implement-dovecot-lmtp
and provide your vision of the issue.
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