Configuring PostgreSQL to listen on all IPs

Tested on CentOS 6. Modify the line:

listen_addresses = '*'

In the /var/lib/pgsql/data/postgresql.conf file.

Setting root password on CentOS MySQL install

After installing and starting up mysqld run the following commands to set the root password:

# /usr/bin/mysqladmin -u root password '[password here]'
# /usr/bin/mysqladmin -u root -h [hostname here] password '[password here]'

Common SELinux problems and tasks

List current selinux context labels on files:

[root@machine1:/var/www/html]# ls -alZ
total 124K
drwxr-xr-x. root   root   system_u:object_r:httpd_sys_content_t:s0 ./
drwxr-xr-x. root   root   system_u:object_r:httpd_sys_content_t:s0 ../
drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 administrator/
drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 bin/
drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 cache/
drwxr-xr-x. apache apache unconfined_u:object_r:httpd_sys_content_t:s0 cli/
...


Change the selinux context:

[root@machine1:/var/www/html]# chcon -Rv --type=httpd_sys_content_t ./*
changing security context of `./administrator/templates/hathor/less/forms.less'
changing security context of `./administrator/templates/hathor/less/buttons.less'
...


Enable Apache to make outbound database connections:

[root@machine1:/var/www/html]# setsebool -P httpd_can_network_connect=1

Enable Apache to use sendmail:

[root@machine1:/var/www/html]# setsebool httpd_can_sendmail 1

Finding the CWD (current working directory) of a running process

Luckily, due to the UNIX philosophy of "everything" is a file, makes it rather trivial to find what the current working directory is. You just need to look at the symbolic "cwd" link under the process directory:

# ls -al /proc/[process number here]/cwd lrwxrwxrwx 1 build build 0 Oct 18 12:29 /proc/2506/cwd /root/run