On 1.3.2012, at 10.44, Joseph Tam wrote:

I would like to run various doveadm commands that involves all (mail) users like

doveadm expunge -A mailbox Trash savedbefore 30d

but any doveadm command that uses "-A" to iterate through all users will stop processing at the first account with UID<first_valid_uid.

doveadm(sysdaemon): Error: user sysdaemon: Couldn't drop privileges: Mail access for users with GID 5551 not permitted (see first_valid_gid in config file, gid from userdb lookup). doveadm(sysdaemon): Error: User init failed doveadm: Error: Failed to iterate through some users

However, these accounts are system accounts (locked password, no shell) and are in userdb to provide UID<->name mapping for utilities like ls, chown, etc.

What userdb are you using? userdb passwd should already skip users that aren't in the valid range. And what Dovecot version are you using?

On 1.3.2012, at 10.44, Joseph Tam wrote:

but any doveadm command that uses "-A" to iterate through all users will stop processing at the first account with UID<first_valid_uid.

doveadm(sysdaemon): Error: user sysdaemon: Couldn't drop privileges: Mail access for users with GID 5551 not permitted (see first_valid_gid in config file, gid from userdb lookup). doveadm(sysdaemon): Error: User init failed doveadm: Error: Failed to iterate through some users

And one more thing: Does it really even stop there? Looking at the code it's supposed to log an error and continue to next user. Note that it says "Failed to iterate through SOME users".