Category Archives: System Administration

This is why there are 32 bit packages on 64 bit Linux Centos

I just installed a new server with Linux Centos 64 bit installed and noticed that actually some 32 bit packages was also installed when I’m running yum upgrade. There was nothing wrong in YUM configuration that I can find.

It turns out that the reason for those 32 bit packages being installed is that Centos follow the upstream source, hence the 64 bit (x86_64) installation by default will also install 32 bit packages. Since I want to have pure 64 bit system then I remove all 32 bit packages that installed on my server and set the exclude option so that 32 bit will not installed by yum command.

To remove all 32 bit packages run the command:

Continue reading This is why there are 32 bit packages on 64 bit Linux Centos

Modify the Maximum Emails a Domain Can Send per Hour

On Cpanel’s Tweak Settings you can limit the maximum each domain can send out per hour. The problem is that this limit also applies to Mailman mailing list hence causing problem for mailing list owners.

The problem happen when the mailing list has members more than the maximum number of email a domain can send per hour. Once the mailing list hit the max limit, the emails start to be bounced back or dropped by Exim from its queue.

To fix this problem administrator can set a limit for a specific domain on the server by modifying /var/cpanel/maxemails file and add the domain that want its limit to be override:

Then run /scripts/build_maxemails_config to apply the new limit.

Disabling Zimbra View Mail Button on Administrator Console

I’ve been searching for a solution to disable the “View Mail” button in Zimbra’s Administrator control panel. I think this “View Mail” button is not necessary and further more it is privacy breach as administrator can see all emails inside an email account.

The new version 6.0 Network Edition seems to be able to do that as it already has Role Based delegation. However, since there are only less than 10 persons that going to use the mail server, I don’t think NE edition is necessary for me.

Currently I’m testing the open source edition of Zimbra 6.0 and have been looking at its code, but unfortunately I can’t find a way to disable or at least hide that “View Mail” button.

I joined the Zimbra forum and shoot a question there but it seems the community has no idea either on how to disable it. Zimbra is open source so I think it should be able to be modified, it just a matter of removing a button from its GUI, it’s not changing the functionality of its core code.

I’ll spend some more time to investigate on how to do this and post the result on next blog post.

Install rTorrent Using CURL in Different Path on Centos Linux

After I posted an article titled “Installing libTorrent and rTorrent on Linux Centos” one of my reader have a concern about dependencies as Centos already have older Curl installed by default.

One way to avoid dependencies problem with Curl is by compiling the newest version to another directory and then compile rTorrent to use that Curl installation and not the old Curl installed by default on Centos. Below is the step-by-step how to install rTorrent with Curl installed in another directory:
Continue reading Install rTorrent Using CURL in Different Path on Centos Linux

Installing libTorrent and rTorrent on Linux Centos

As requested by one of my blog reader, I write this libTorrent and rTorrent installation tutorial :) I’m installing libTorrent and rTorrent on a Xen based VPS with Linux Centos 5.4

From the project’s website:

LibTorrent is a BitTorrent library written in C++ for *nix, with a focus on high performance and good code. The library differentiates itself from other implementations by transfering directly from file pages to the network stack. On high-bandwidth connections it is able to seed at 3 times the speed of the official client.

To install libTorrent and rTorrent first we install the compiler and dependencies required Continue reading Installing libTorrent and rTorrent on Linux Centos

Ubuntu 9.04 Keyboard Mapping Problem on Tight VNC

After logged in to VNC server, I get problem with the keyboard mapping on Ubuntu 9.04. When I type “abcdefghij” I get “asdfghjkl;“. After searching on Google, the problem was submitted as a bug and the work around is by adding:

In VNC’s xstartup file:  $HOME/.vnc/xstartup

You have to add the line export XKL_XMODMAP_DISABLE=1 before /etc/X11/Xsession or gnome-session (in case you use GNOME)