Work experience

After Gentoo update (the big one:) crontab stopped working to non-root users.
I use crontab as postgres user to make my daily database backups. After checking messages log in /var/log/messages I found this line:

cron: Authentication service cannot retrieve authentication info.

Problem is that after pam update something wrong went to passwd/shadow files and postgres user had wrong entry. To fix this, simply use command in root shell:

From man page of pwconv:

pwconv creates shadow from passwd and an optionally existing shadow.
So pwconv fixes this problem, and cron for postgres works again.
The other problem, why postgres or other non-root user crons doesnt run my occur if you don’t add those users to cron group. To add postgres user to cron group use this command:

More info about shadow/passwd problem after update you can read on gentoo forums:
pwconv+postgres.html
cron+authentication+service+retrieve+authentication.html

I have an old laptop IBM ThinkPad 600. Recently, installed Ubuntu linux on it. There is a little problem. New Ubuntu 6.10 installation works as live cd. So, you boot from live cd, then install it to your PC.

Problem is, that in old laptop there is only 128MB ram, and during ubuntu boot, it hangs (not enough ram).
The sollution is to download ubuntu-6.10-alternate-i386.iso. It’s alternate installation cd, where you can choose text based install.

There are also two good resources about ThinkPad 600x problems and their sollutions on Ubuntu:
http://ubuntuforums.org/showthread.php?t=188736
http://www.mueller.ch.vu/misc/tp600e_en.html
Also, you can check thread on ubuntuforums, where I made a post about “Getting Error After Disc Loads to First Menu”
http://ubuntuforums.org/showthread.php?p=2337274

Sometimes, in kde occurs such a problem. All fonts in menu, applications and so one becomes very small. It occured after my monitor downgrade (resolution changed from 1600×1280 to 1024×768). At first, I tried to increase font size in KDE control center:

( Start (K :) -> Preferences -> Control Center ->Appearence & Themes -> Fonts)

But it didn’t work with non-kde apps.

The sollution is to change dpi in kdm options. Edit /etc/kde3/kdm/kdmrc and change line ServerArgsLocal=-nolisten tcp to

ServerArgsLocal=-nolisten tcp -dpi 100HTH .
And restart your kdm (Ctrl+Alt+Backspace)

In my sample, there is 100dpi otion. If result doesn’t satisfy your needs, play a little with this number (75, 170 etc.)

If you need to write custom rules to spamassassin and trere are a few of them. For example, you want to get rid of some spam which goes through spamassassin and mail’s score almost reaches score, to be marked as spam. Simply add rules to /etc/mail/spamassassin/local.cf

For example:

In example there is rule PASTAS_OPT which adds score 1 to e-mail if there is obfuscated sentence in message body Remove your email. The dot symbol match any character (except newline), so sentences like “Re-move y our e~mail:” will be found, and score will be increased. Symbol “i” means that sentence (string) is case insensitive. All rules are written in perl regexp form. More abour regexps you can find here: http://www.perl.com/doc/manual/html/pod/perlre.html
Do not add big scores to one rule. Better write more rules with smaller score.
After custom spmassassin rules are written, check for correct syntax:

OR

for more info on errors

However spammers find more and more typos and methods of obfuscation to bypass such rules. So I recommend you to use Rules Du Jour and sa-update scripts. There are both in gentoo portage. Allso when you get spam, send those spam mails to your mail server (in examle /tmp/spam/) and train spamassassin’s bayesian filter:

Allso it is important to train bayesian filter with good e-mails. Upload good emails to server (in examle /tmp/ham/) and train filter, showing how good mails looks like:

Finaly, restart spamd or amavisd (depends on your mail/antispam configuration)

Windows 98SE supports USB hotplugging, but does not have generic usb storage driver. Recently I found sollution here: http://www.technical-assistance.co.uk/kb/usbmsd98.php.
Just download that generic driver and install. I did testing on some usb keys and dictophone olympus ws-300m. It worked like a charm :)