The Helpdesk For I.T. Administrators
Changes you make to iptables firewall rules only exist for the current boot, and if you don’t save the config, you will loose any changes upon rebooting. CentOS 6 blocks most incoming ports by default, so you will generally have to make changes to the firewall if you install any new packages. Thankfully CentOS 6 …
There are many Linux distributions out there, all with their slight differences. It’s sometimes its hard to determine what distribution you are current using, assuming you weren’t the one who installed it. The commands below can be used to determine the Linux distribution you are using, and in most cases, what version. Generic check: cat …
To determine what version of the Linux kernel you are currently using, you can use the uname command as per the examples below. $ uname -a This will output the host name of the computer, Kernel version, and the CPU architecture. Example output: $ uname -a Linux localhost.localdomain 2.6.32-279.19.1.el6.x86_64 #1 SMP Wed Dec 19 07:05:20 …
The tail command which is found on almost all Linux distributions is used to output the last part of files. There is a parameter for the tail command that allows you to monitor a file, and continually output new lines from the file as they are added. This is especially handy for monitoring log files …
A common requirement on any operating system is to be able to view the total size of a list of folders and files on the file system, and be able to sort the list by size. Generally this isn’t straight forward to do. The commands below can be used to do just that. Display folder …
If you are writing an iOS application that needs to communication with the Apple APN (Apple Push Notification) servers, or if you are are an end user behind a strict firewall, the information below can be used to correctly configure the firewall rules to allow access.
This ‘how to’ guide will step you through the process of installing FreeNAS 8 to a USB memory stick using a Windows computer. This can be a handy too if you have a system that has crashed, and you just want to get it back up and running so you can copy files off of …
By default, an Exchange server will try and send emails to a smart host using port 25. Unfortunately, there is no option to change the port number within the Exchange Management Console. This howto guide will show you how to change this to a different port number. This will be done using the Exchange Management …
This howto guide will step you through the process of setting up your Microsoft Exchange 2010 Server to send emails via a smart host. The use of a smart host can be useful when the Exchange server cant directly send emails to external mail server. This might be due to firewall rules, ISP filters, or …
This howto guide will step you through how to restore a MySQL database from a backup file, using the MySQL client command line tools on a Linux machine. Backing up databases is important, but it is useless if you don’t know how to restore the backup. Regular restores should be done to ensure that your …