There are times whenever you plan to upgrade your computer’s (or server’s) hardware, but you don’t know or you forgot what you bought a year a go. There are few possibilities to get your information, although some comes as package with most of the modern distros, where others need to be installed from source or from external to your distribution repository.
Having your network interface card auto-negotiate the connection speed sometimes causes big troubles in terms of data packet loss. Your best friend in such situations is ethtool which is really easy to use, once you get to know it.
Have you tried to send a mail to one of your WHM accounts and you didn’t got anything in the inbox? A client of yours tells you he haven’t been receiving mails for some time, although he has been notified he will get mail? All of a sudden you receive bounce-back mails which includes “550 Unrouteable address” or “550 Sender verify failed” message? This could be because of multiple causes
If you have read my previous posts about using ssh config file and passwordless ssh login probably you already got your config file filled with host declarations and you got your keys (one for each server) in place. Here is the solution for a very common problem, yet a problem which is widely spread nonsense on the net. This problem occurs when you use ssh key authentication. A lot of websites states that you have to add your key files with a “identifyfile” directive in the ssh config file, which is yet another nonsense. The correct directive is “IdentityFile”. A lot of websites (blogs and forums) suggests that you increase the connection attempt limit of your servers to avoid this. But that is WRONG! Just think about it….
You can easily create short-cuts for servers you are using frequently, by creating a local configuration file for SSH. By using such configuration file, you can configure more advanced options for your SSH connections.
To do this, we will be using a terminal application (default available terminal application for gnome is gnome-terminal, of course you can use guake as well).
When you get a dedicated server, you have one main and shared IP address, which is being used by every non-reseller account for which you do not chose dedicated IP. There is no functionality in WHM which would allow you to have multiple shared IP addresses on the same account, but that is achievable via SSH and some editing of cPanel configuration files.
Installed Gnome 3 with your distribution’s automatic upgrades, or you just installed your new system with Gnome 3 and you don’t know how to automatically start applications when you login in the desktop environment? This had me puzzle for a while as well. The solution is truly simple, also it’s being provided by applications you’ve already seen in older Gnome releases, it’s just they do not have the usual “shortcut” in your gnome-shell.
We will start with installing alacarte (if you don’t have it already of course).
Using “sudo” instead of “su” for gnome desktop applications is not really hard to do, but it took me a while to find and understand the way to do it. Here is what I found in a serverfault.com
Maybe some of you searched how to convert mp3 to audo format which can be listened on any cd player. Actually, the audo format which most people knows as “cda” is just “wave” file (file with .wav or .aiff extension). The linux command to convert a lossy mp3 to loseless wav is pretty simple:
Whoever had to rename dozens of files in a folder knows how painfully slow that can be. Here is a one line bash script how to do this fast.
