25th June 05:15
open files: cannot modify limit: (ulimit -n) error
I have an Itanium based system running Red Hat Enterprise Linux AS
release 4 (Nahant Update 1).
The contents of /proc/sys/fs/file-max is: 1660043
The contents of /etc/security/limits.conf contain:
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
oracle soft stack 1024
oracle hard stack 32768
The contents of /etc/pam.d/sshd :
auth required pam_stack.so service=system-auth
auth required pam_nologin.so
account required pam_access.so
account required pam_stack.so service=system-auth
password required pam_stack.so service=system-auth
session required pam_stack.so service=system-auth
session required pam_limits.so
session optional pam_console.so
If I `sudo su - oracle' and then type:
ulimit -n 65536
I get the following error returned:
-bash: ulimit: open files: cannot modify limit: Operation not
On the other hand, if I am root, and then `su - oracle' and then type
`ulimit -n 65536' the error is not generated, and the open files limit
is set to 65536 as can be seen from the output from `ulimit -a'.
I know the bash man page states the following for the -n switch for
-n The maximum number of open file descriptors (most systems do not
allow this value to be set)
Although this may be true, you can see that I was able to use the -n
switch and change the open files from its default value of 1024 to the
hard limit of 65536 set in the limits.conf file.
I have googled and have seen a few posts dealing with this similar
issue, but I have not seen a solution or explanation for the problem.
Does anyone know what is causing this error and how to fix it?