RPM packages are compiled by vendors with too few file descriptors (1024), which might cause the following messages to appear in
Segmentation fault (11) [warn] make_sock: problem listening on port 443, file descriptor (1068) larger than FD_SETSIZE (1024) Unable to open logs Too many open files
This is a common Apache issue on servers with many Virtual Hosts configured. See this article for more information: http://httpd.apache.org/docs/2.0/misc/descriptors.html.
NOTE: Since Plesk 8.2.0, up to 900 domains can be hosted on the OS vendor Apache build without the system packages recompilation described in this article. If the Piped Logs feature is enabled on the Plesk server, see 2066.
NOTE: This article is for Linux operating systems that have an RPM packages structure, such as RHEL, Fedora, CentOS, and SuSE.
For details on the Debian system, please see this article.
For details on the FreeBSD system, please see this article.
NOTE: Plesk requires many server applications that are not Plesk software. For example, the Apache web server, MySQL server, PHP module and binaries, and many other items are not compiled by Parallels and are not provided by Parallels; however, standard system RPM packages from the operating system vendor are used by Plesk "as is." This allows the administrator to upgrade and recompile such packages with the desired options. This article is written to help administrators of Plesk configure their OS and system packages that are not included in the Plesk distributive to use with a large number of hosted domains.
You need to recompile related applications and libraries, such as openssl, apache, imap, PHP, etc., from the source RPMs with an increased "FD_SETSIZE" value. Please follow these steps:
Make sure that the system allows you to open enough files:
# /sbin/sysctl fs.file-max fs.file-max = 131072
If the value of fs.file-max is quite small (several thousand or so), it should be changed by adding the following lines to /etc/sysctl.conf:
fs.file-max = 131072
and running the shell command:
# /sbin/sysctl -w fs.file-max=131072
NOTE: If you are running Virtuozzo, you have to adjust fs.file-max on the Hardware Node and it will be applied to all VEs.
You should have the glibc-kernheaders and glibc-headers packages installed. They can be taken from the operating system distributive CD or from your operating system's download sites. Edit the FD_SETSIZE value in the typesizes.h and posix_types.h files that can be found with the following:
# find /usr/include/ -name typesizes.h # find /usr/include/ -name posix_types.h
and set it as follows:
#define __FD_SETSIZE 65536
libc-client-devel-*.src.rpm(if such RPM is installed)
Recompile openssl first. For example:
# /usr/bin/rpmbuild --rebuild openssl-0.9.7a-35.src.rpm
Install the compiled openssl RPM with the following command line:
# rpm -Uvh --force /usr/src/redhat/RPMS/i386/openssl-0.9.7a-35.i386.rpm
Repeat the same actions for cURL.
Recompile and install apache:
# rpmbuild --rebuild httpd-2.0.51-2.9.src.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/httpd-2.0.51-2.9.i386.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/httpd-devel-2.0.51-2.9.i386.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/mod_ssl-2.0.51-2.9.i386.rpm
Recompile and install the libc-client library, which is provided by the imap or libc-client-devel packages (depends on the OS). You must recompile one that is installed in the system. For example:
# /usr/bin/rpmbuild --rebuild imap-2002d-3.src.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/imap-devel-2002d-3.i386.rpm
# /usr/bin/rpmbuild --rebuild libc-client-devel.src.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/libc-client-devel.rpm
Recompile and install PHP. For example:
# rpmbuild --rebuild php-4.3.10-2.4.src.rpm # rpm -Uvh --force /usr/src/redhat/RPMS/i386/php-*
ulimit -n 65536 command to the /etc/rc.d/init.d/httpd and /usr/sbin/apachectl apache startup scripts before other commands.
/usr/sbin/suexec with a Plesk one:
# cp /usr/local/psa/suexec/psa-suexec /usr/sbin/suexec # /etc/init.d/httpd restart
Use the following commands for Plesk versions earlier than 7.5:
# cp /usr/local/psa/suexec/psa-suexec /usr/sbin/suexec # chown root:apache /usr/sbin/suexec # chmod 4510 /usr/sbin/suexec # /etc/init.d/httpd restart