Level 3 Test Review
To Study
Boot Up Issues - initrd, journal, grub
MySQL - replication
PLesk Hacker and database schema
thirdshift wiki
research questions
-check out the VMs that paul set up
Research Questions
1. configure postfix to pass mail through spamassassin. the rack user should have all spam filtered into a seperate spam folder
http://wiki.apache.org/spamassassin/IntegratedSpamdInPostfix
1. Edit /etc/postfix/main.cf, add: virtual_alias_maps = pcre:/etc/postfix/virtual
2. Edit /etc/aliases, add: scripttarget: "| /path/to/program/to/execute"
3. Edit /etc/postfix/virtual, add: /^[0-9]{10,11}@dev.mblst.com/ scripttarget
4. Restart postfix: service sendmail restart
5. That's it.
2. create an svn repository named 'wp' that contains the wordpress source code in /home/svn. Configure your web server to properly handle svn connections to http://domain/wp
3. configure http://domain (192.168.0.1) to load balance across 192.168.0.2 and 192.168.0.3 with web content out of /home/major and /home/minor respectively. Using iptables 60% of the traffic should be served from /home/major
4. configure vsftpd to listen on ports 21, 2121, 8888. no iptables.
- need to use multiple process each with different vsftpd.conf files
5. install wordpress into /home/rackwp and setup http://wp.domain.com on 192.168.0.1. Configure squid in reverse proxy configuration on port 9999 to be the front end for the wordpress blog.
6. configure a second instance of mysql to listen on port 3307. create and configure the 'rackdb' to be replicated from mysql server on port 3306 to new instance on 3307
Break Fix #1
(error)
root (hda)
Error 23: Error while parsing number
Boot to: linux rescue
# fdisk -l
# e2label // to see labels used in fstab & to find boot and /
-check /etc/fstab to see mount points
// grub.conf
title CentOS (2.6.18-53.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-53.el5 ro root=LABEL=/1
initrd /initrd-2.6.18-53.el5.img
THEN, a new issue came up on boot.
(error)
Creating root device.
Mounting root filesystem.
ext3: No journal on filesystem on sda6
mount: error mounting /dev/root on /sysroot as ext3: Invalid Argument
Setting up new filesystem.
Setting up new root fs.
setuproot: error mounting
Switching to new root and run init.
SOLUTION: Rebuild the journal on /dev/sda6
Break Fix 2
(error)
RAMDISK: Couldn't find valid RAM disk image starting at 0.
VSF: Cannot open root device "LABEL=/" or unknown-block(0,0)
Please append a correct "root=" boot option
Kernel panic - not syncing : VPS : Unable to mount root fs on unknow-block(0,0)
# mkinitrd -f /boot/initrd-`uname -r`.img `umane -r`
-Check /etc/inittab for the right runlevel
id:3:initdefault:
Break Fix 4
(error)
mount: count not find file system '/dev/root'
# fdisk -l
# parted /dev/sda print // for partition sizes
# e2label /dev/sd1
# cat /etc/fstab
LABEL=/ /
# e2label /dev/sda6 /
Issue 2: check the permissions on /bin/sh (/bin/bash); they were set to 000.
Break Fix 5
(error)
_
(just a black screen with curser)
- Nothing in /boot, no GRUB installed
# grub-install --root-directory=/ /dev/sda
OR
Alternative grub setup. see link.