I sometimes get an error when I want to login via ftp. The error is
500 OOPS: setuid. I can't figure out why this happens sometimes, but sometimes it doesn't. I've se the limit of processes per user to unlimited, but this still happens. I'm running Fedora Core 10.
From the vsftpd wiki:
I'm getting: 500 OOPS: setuid - Why?
setuid(2)sets the user identity for a process. If the user in question has run out of processes --
ulimit(1)-- this will fail, and vsftpd will return said error.
This behaviour is most common seen on embedded devices, where the number of processes a user is allowed to spawn is actually limited. On most common-place Linux distros this is set unlimited.
You can verify this by checking under what username vsftpd is running with
ps -ef | grep ftp.
Then log in as this user with the
su - [username, for example root] command, and check the limit for the number of processes with
On my CentOS machine the root account was limited to 2047 processes.
Raise this number if needed with
ulimit -u [number of processes, for example 5000], or use
ulimited -u unlimited for an unlimited number of processes.