Dovecot doesn't run bacause too many open files

[sarra]

Hi everybody,
I have installed SLES 11 as IMAP server with dovecot11-1.1.17-1.1. I use the default configuration in /etc/dovecot/dovecot.conf.

The problem is: after a period, the clients email lose the connection and in /var/log/auth.log I find the error below. The authentication is done with winbind to an Active Directory.

The output of ulimit command is

core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 16382
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) 1634208
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 16382
virtual memory (kbytes, -v) 4892480
file locks (-x) unlimited


and when I get the errors I have as output of the command "lsof |grep dovecot-a |wc -l"

1248

or similar, more than 1024 however.

If I try to put the command "ulimit -n 2048" in the dovecot's start script I get other errors for winbind.

Any suggestions ?


============
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_env.so): /lib64/security/pam_env.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_env.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_unix2.so): /lib64/security/pam_unix2.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_unix2.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_krb5.so): /lib64/security/pam_krb5.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_krb5.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_winbind.so): /lib64/security/pam_winbind.so: cannot open shared object file: Toomany open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_winbind.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_localuser.so): /lib64/security/pam_localuser.so: cannot open shared object file:Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_localuser.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_ldap.so): /lib64/security/pam_ldap.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_ldap.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_pwcheck.so): /lib64/security/pam_pwcheck.so: cannot open shared object file: Toomany open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_pwcheck.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_succeed_if.so): /lib64/security/pam_succeed_if.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_succeed_if.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_deny.so): /lib64/security/pam_deny.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_deny.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_limits.so): /lib64/security/pam_limits.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_limits.so
Nov 4 11:15:05 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_umask.so): /lib64/security/pam_umask.so: cannot open shared object file: Too many open files
Nov 4 11:15:05 zeus dovecot-auth: PAM adding faulty module: /lib64/security/pam_umask.so
Nov 4 11:15:07 zeus dovecot-auth: PAM unable to dlopen(/lib64/security/pam_env.so): /lib64/security/pam_env.so: cannot open shared object file: Too many open files