This is just an easy one-liner to install the Danish language pack for OpenOffice.org in recent versions of Fedora Linux:
Recently I needed sendmail and sendmail-devel to compile some software, but when I installed Sendmail, it decided to make itself my preferred MTA – and I suddenly got the same feeling of powerlessness that accompany running Microsoft Windows.
Newer Linux distributions offer the Alternatives system, which basically lets you choose between different installed software that serve the same purpose. If you’re running Sendmail and Postfix like me, you can use Alternatives to pick which MTA you prefer to use:
1 | -- |
config mta
There are 2 programs which provide ‘mta’.
Selection Command
1 | ----------------------------------------------- |
* 1 /usr/sbin/sendmail.sendmail
+ 2 /usr/sbin/sendmail.postfix
Enter to keep the current selection[+], or type selection number: 2
Today I lost my Ethernet devices, probably as a result of upgrading the apartment server from Fedora 9 to Fedora 10. The culprit turned out to be the service responsible for dynamic device management – udev. These symptoms started showing up in the logfile:
The udev daemon creates and renames devices according to configuration files in /etc/udev/rules.d/ called rules. One of them – 70-persistent-net.rules – specifically handles network devices. This file was screwed up badly by Anaconda, and had dupes and network devices from a previous hardware configuration. I cleaned up this file, so it had only contained rules that matched the hardware addresses of the installed network devices:
Various external “plug-and-play” helpers may add newly found network devices to this file, so if your network devices start changing names, you might want to check /etc/udev/rules.d/70-persistent-net.rules.
These are the install notes for my Fedora 10 install on my workstation at the office:
Enable access to both the free and the nonfree repositories at RPM Fusion and run an upgrade:
http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm
Make sure the system is crisp and updated with the new repositories:
Install GStreamer plugins with stability/license issues, including support for AAC, A52, SID, MPEG2, MP4, H.264, DVD navigation etc.:
Install various alternate video players:
Install various video encoders:
In time of writing, Adobe’s Flash plugin isn’t available as RPM – at least not the lastest beta version for x86_64 – so download it from Adobe Labs, unpack and drop libflashplayer.so in ~/.mozilla/plugins/. Make sure you’ve removed any trace of NSPluginWrapper first. Example (this is a single-user install, so don’t run as root):
Random browsing takes you weird places, and suddenly I found myself reading up on tweaks for the Linux IPv4 TCP stack – many of them actually recommended by Sun. Your mileage may vary, and you probably should read up on every single option before you apply it. All options go in /etc/sysctl.conf.
Allow the TCP stack to reuse sockets in the TIME-WAIT state:
TCP Timestamps are enabled per default, and enables calculation of RTT in a more accurate way (see RFC 1323) than the retransmission timeout. IBM suggests this should be enabled for performance, but others suggest disabling it and saving 12 bytes header overhead. We’ll leave it on:
Enable selective acknowledgment, which improves performance by selectively acknowledging packets received out of order (causing the sender to retransmit only the missing segments). Should be enabled for wide area network communication, but it can increase CPU utilization. Also enable Forward Acknowledgment (FACK), which operates with Selective Acknowledgment (SACK) to reduce congestion:
To use large packet windows (over 64Kb), you should enable window scaling as defined by RFC 1323:
Lowering the FIN Timeout value will shorten the TIME_WAIT state, freeing up resources for new connections. It is recommended when running applications that constantly create a lot of new connections – ie. a web server. The default is 60, and Sun recommends a value in the 15-30 range.
Tweak the TCP KeepAlive values:
The default maximum for send/receive windows is 128Kb and it’s recommended to boost this to 8Mb:
Also tweak the IPv4 rcv/snd buffers to use a maximum of 8Mb:
If you’re using a lot of connections, you should make more local ports available. Default range gives a total of 28232 ports available. Increasing this range to 4096-65535 will give you 61439 local ports:
Apart from hopefully boosting overall network performance, the tweaks above also lowered the number of sockets in the TIME_WAIT state from 300 to around 50.
Any comments and/or corrections are welcome.
Sources:
