This Is Your Brain On Informatics: Common Pathnames

/etc/init.d/[service] [operation]

This "pathname" is actually a script that causes the initiate daemon (that constantly stays in memory) to act on a service that has been input. After the service, an operation can be input in from one of the following:

• start
• stop
• reload
• restart
• force-reload

For our purposes, the only services that we know that this script can act on are as follows:

• nginx
• mysql
• php5-fpm
• denyhosts

/etc/network/interfaces

This file will allow modification of the networks that are on a computer/server. It can be used to set up a static IP address, but a virtual machine will need to use a dynamically acquired IP. This network will be necessary for allowing the machine to allow ssh capabilities. Below are the steps for setting up a second network on a virtual machine (one more is necessary in addition to the one that is already on the machine).

1. Access the above pathname with pico ( pic /etc/network/interfaces)
2. Below the first network (indicated by eth0), copy the first network, replacing eth0 with eth1

   auto eth1

   iface eth1 inet dhcp

3. Reboot the machine
4. Determine the new IP address of the eth1 network by one of the following
   1. After logging in, check the IP next to the eth1 network
   2. Type "ifconfig" into the command line and check the IP next to the "inet addr:"

/etc/hosts.deny

This file can be accessed via pico or any other text editor in order to manage the IP addresses that have been blocked from accessing your virtual machine (including your own if it accidentally happens). Once you are in the file, delete the IP address (possibly your IP address) at the bottom of the file that you no longer wish to restrict.

/etc/host.allow

This is a file that is similar in nature to the hosts.deny file in that IP addresses can be input into the file. However, IP addresses that are input into this file will be allowed access to the nginx web server and prevented from being automatically added to the hosts.deny file (this will still occur if the login attempts from the same IP address are exceeded). This file should only be used as a last resort if denyhosts continually (and erroneously) adds your personal IP address to the hosts.deny file. An alternative is using aptitude to remove the denyhosts firewall; however, this is not recommended for a live server.