Linux File Max connections --- bash: ulimit: open files: cannot modify limit:

Linux File Max connections --- bash: ulimit: open files: cannot modify limit: Operation not permitted Problem description: logon system error,-bash: ulimit: open files: cannot modify limit: operation not permittedLast login: Thu Aug 23 14:42:27 2012 from 10.6.90.41-bash: ulimit: open files: cannot modify limit: Operation not permitted-bash: ulimit: open files: cannot modify limit: operation not permitted
Actually, when executing the ulimit command, the following error occurs: www.2cto.com-bash-3.2 $ ulimit-acore file size (blocks,-c) 0 data seg size (kbytes,-d) unlimitedscheduling priority (-e) 0 file size (blocks,-f) unlimitedpending signals (-I) limit 4960max locked memory (kbytes,-l) 32max memory size (kbytes,-m) unlimitedopen files (-n) 1024 pipe size (512 bytes,-p) 8 POSIX message queues (bytes,-q) 819200real-time priority (-r) 0 stack size (kb Ytes,-s) 10240cpu time (seconds,-t) unlimitedmax user processes (-u) 16384 virtual memory (kbytes,-v) unlimitedfile locks (-x) unlimited-bash-3.2 $-bash-3.2 $ ulimit-u 16384-n 65536-bash: ulimit: open files: cannot modify limit: operation not permitted-bash-3.2 $ configuration is normal-bash-3.2 $ cat/etc/security/limits. conf www.2cto.com # add by wj for racoracle soft nproc 2047 oracle hard nproc 16384 oracle Soft nofile 1024 oracle hard nofile 65536 grid soft nproc 2047 grid hard nproc 16384 grid soft nofile 1024 grid hard nofile 65536-bash-3.2 $ cat/etc/pam. d/login # add by wj for racsession required pam_limits.so-bash-3.2 $-bash-3.2 $-bash-3.2 $ cat/etc/profile # add by wj for racif [$ USER = "oracle"] | [$ USER = "grid"]; thenif [$ SHELL = "/bin/ksh"]; thenulimit-p 16384 ulimit-n 65536 elseulimit-u 16 384-n 65536 fiumask 022fi Cause Analysis: because the problem occurs after the openssh upgrade and only ssh logon occurs, it is basically suspected that www.2cto.com is related to ssh. solution: the problem is finally solved, it is indeed an ssh Version problem vi/etc/ssh/sshd_config set UseLogin to yes, # UseLogin noUseLogin ye restart ssh service sshd restartUseLogin. the specific meaning of this is as follows, after reading this, I do not quite understand whether UseLogin uses login (1) During the login process of interactive sessions ). The default value is "no ". If this command is enabled, X11Forwarding will be disabled because login (1) does not know how to handle xauth (1) cookies. Note that login (1) is forbidden for remote command execution. If UsePrivilegeSeparation is specified, it is disabled after authentication.