Migrating /etc/ethers into LDAP

If you are using /etc/ethers than you can move it into your LDAP. First take a look at your /etc/ethers:

# cat /etc/ethers
00:1B:21:02:96:56    192.168.1.70
00:30:05:c5:2a:ba    192.168.1.73
98:FC:11:79:37:76    192.168.1.69

Migrating /etc/hosts into LDAP

If you are using /etc/hosts than you can move it into your LDAP. First take a look at your /etc/hosts:

# cat /etc/hosts
127.0.0.1        localhost
192.168.1.70     blog01
192.168.1.73     dc01
192.168.1.69     wlan01

Backing up and restoring your LDAP

If you're using LDAP with BDB backend then you have two chances to backup your LDAP server:

1. from any client via ldapsearch
2. on the LDAP server via slapcat

Get the current used memory with ps

Last time I had a customer complaining about his 72GB RAM machine that it was swapping. Then he told me that all processes were using 0% RAM. He showed me something like this:

# ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
...
oracle    4539  0.0  0.0    708 48264 ?        Ss    2008  16:23 ORACLE
...

SmartPCI56(UCB1500) 56K Modem with Slackware

I got another Modem PCI card - again. This time something like this:

# lspci
...
00:09.0 Modem: Philips Semiconductors SmartPCI56(UCB1500) 56K Modem (rev 01)
...

PCTel Inc HSP MicroModem 56 with Slackware

Yesterday I got an old PCI Modem card, something with pctel anything. I was wondering if I could get it to run, so I did some research on the Internet and found the pctel software for Linux. The disapointment was that i will only compile on 32bit machines. Anyway, I setup my old Athlon 800MHz desktop with the pctel card and installed the current Slackware release (13.37). Then I donwloaded the driver from http://linmodems.technion.ac.il/pctel-linux/welcome.html:

LDAP for Slackware Linux

When you work with Slackware Linux and try to authenticate with LDAP then you will figure out that it won't work. This has a simple reason: to authenticate with LDAP you need PAM, but Patrick Volkerding refuses to put PAM into Slackware because of security reason - AFAIK. Here is a small description how to setup Slackware for authentication with LDAP. But be aware: I am doing some things here that you shouldn't do under normal circumstances.

Available disk space in Linux

One of the basic tools to monitor your harddisks and partitions is df - disk free. It shows you a couple of information about how your harddisk is used. A sample output maybe like this:

# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root            251915124  33553292 205565260  15% /
...

Available, used and free memory in Linux

free will show the used and available memory. The default output could be like this:

# free
             total       used       free     shared    buffers     cached
Mem:       3792504    1499452    2293052          0      48460     586436
-/+ buffers/cache:     864556    2927948
Swap:      4200992          0    4200992

Configuring network and SSH in NetBSD

I have set up my old workstation (AMD Duron with 1.2GHz and 512MB of Ram) with the current NetBSD release 5.1 to play a little around with it. I installed it in a VM (without any networking hardware) directly on the harddisk and after installation I placed the harddisk into the computer. When the OS is booted, I took a look at the networking hardware: