

There can be various reasons for processes not being able to fork: Note 353529.1: Requirements for Installing Oracle 9iR2 64-bit on RHEL 4 x86-64 (AMD64/EM64T).Note 339510.1: Requirements for Installing Oracle 10gR2 RDBMS on RHEL 4 on AMD64/EM64T.Such an article should be in Oracle Metalink, for example: Use Oracle Installation Guide for your version of Oracle for this and complete the section related to changes in /etc/security/nf and other files. Double check, if the modifications required was done on your system. Oracle Installation Guide usually requires some modifications in /etc/security/nf, /etc/profile and other files related to the numbers of processes. There could be an Oracle database running on the server. Setting nproc in /etc/security/nf has no effect in Red Hat Enterprise Linux 6 In RHEL6, also check /etc/security/limits.d/nf. Kernel.pid_max must be larger than the total number of simultaneous threads and processes.

For example, if the above result is 32,000, then increase kernel.pid_max to 65534.In RHEL6 use cgroups to limit access to resources for processes, please refer to the separate knowledge base article on cgroups.Ĭheck the total number of threads and processes running on the server: ~]# ps -eLf | wc -l Consider running valgrind against the application, which will report any memory leaks that are found, or contact your application vendor. When the system runs into an out of memory situation, locate the application with the memory leak. For example, here is an example of /etc/security/limits.d/nf file. The limit can be increased for a specific user or all users. When the system runs into a limitation in the number of processes, increase the nproc value in /etc/security/nf or /etc/security/limits.d/nf depending on RHEL version. Raising limits while not fixing the root cause of the process, thread or memory leak may lead to worse, unpredictable consequences. Always confirm that number of processes, threads or memory consumption is expected in your use case before raising any limits. There may be misbehaving services or processes running.There can be various reasons for processes not being able to fork and thus that means there are also various resolution: Nov 24 13:00:18 localhost udevd: udev_event_run: fork of child failed: Resource temporarily unavailable Nov 24 12:59:14 localhost multipathd: fork failed: Resource temporarily unavailable Similar fork failed: Resource temporarily unavailable error are logged by other processes also: Nov 24 12:59:14 localhost multipathd: fork failed: Resource temporarily unavailable The following errors are observed in /var/log/messages: Nov 24 19:08:51 localhost sshd: error: fork: Resource temporarily unavailable

Nov 24 19:14:46 localhost sshd2: Disconnecting: fork failed: Resource temporarily unavailable Nov 24 19:06:04 localhost sshd2: Disconnecting: fork failed: Resource temporarily unavailable The following errors are seen in /var/log/secure: Nov 24 19:01:45 localhost sshd2: fatal: setresuid 20054: Resource temporarily unavailable
