OPS335 Archiving Lab

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Revision as of 11:17, 1 April 2012 by Paul.W (talk | contribs) (Automating System Backup)
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Automating System Backup

This lab will show you how to set up a Fedora installed system to be used for file backups.

Important.png
Prerequistites:
Your hard drive should have Fedora 16, 64 bit Live edition already installed.
You should have at least one VM installed: also Fedora 16, 64 bit Live edition
Both your host and guest should have default firewalls enabled.
Both host and guest should have all software updated.
Ensure the clocks on both machines are set to the correct date and time.
  • Your virtual system will be used to backup files from the host machine.

Using rsync and cron to automate system backup

  • Login to vm01 as joker and open a terminal window. Then "su -" to root run the following two commands:
mkdir /backup
rsync -avz 192.168.122.1:/etc/ /backup/etc
  • Still on vm01 run this command to verify rsync worked correctly:
ls /backup/etc
  • Notice that when running rsync you had to enter the password for root on f16. To automate this process so that it will run without requiring a password we'll use an RSA public/private key pair for passwordless authentication. To do this we'll have to generate an RSA public/private key pair on vm01. We'll use an openssh command like this:
 ssh-keygen -t rsa
  • when you enter this command just hit ENTER for all the questions. Here's what I got when I ran it on my vm01
 Generating public/private rsa key pair.
 Enter file in which to save the key (/root/.ssh/id_rsa):
 Enter passphrase (empty for no passphrase):
 Enter same passphrase again:
 Your identification has been saved in /root/.ssh/id_rsa.
 Your public key has been saved in /root/.ssh/id_rsa.pub.
 The key fingerprint is:
 f5:07:8c:aa:b6:08:e0:45:81:ca:d6:88:8c:aa:1a:7b root@vm01@localdomain
 The key's randomart image is:
 +--[ RSA 2048]----+
 |       o+++      |
 |    E .ooo..     |
 |     ...o.       |
 |       ...o     .|
 |       .S+ +   o.|
 |        . = . o .|
 |           o +   |
 |          o +    |
 |           . .   |
 +-----------------+
  • Now you'll need to copy vm01's public rsa key over to f16. Still on vm01 use this command (be sure you have the /root/.ssh/ directory on f16 - if you don't then make it first):
 scp /root/.ssh/id_rsa.pub 192.168.122.1:/root/.ssh/authorized_keys
  • Now verify that your new authentication method is working. Still on vm01 try to ssh to f16 as root. You should be able to login without entering a password. If you were successful then move on to the next step, otherwise repeat steps 3 and 4.
  • Install mailx on vm01 if it's not already installed.
  • Now, still as root on vm01, use the command 'crontab -e' to edit root's cron table. Insert the following line:
55 * * * * /usr/bin/rsync -avz 192.168.122.1:/etc/ /backup/etc 
  • At 55 minutes past the hour rsync should synchronize the /etc/ directory of f16 to the /backup/etc/ directory on vm01. If this time has passed and you don't want to wait an hour for the next time rsync runs, just edit root's cron table on vm01 and enter another time for the backup to take place.
  • You should convince yourself that /etc/ is being backed up by adding some file (say 'touch /etc/junk' on f16) to /etc and then see if it was indeed copied to vm01.
  • After the cron job runs, root on vm01 should have received an email containing the output of the cron job. Verify this by using the mail command to check root's mail on vm01.
  • Finally, edit root's cron table on vm01 and add another record to backup the /home directory of f16 to /backup on vm01 once each week at 2am on Saturday.

Using syslog to route log files to a remote host

  • On your host machine (f16) edit /etc/rsyslog.conf and make the following change:
#*.* @@remote-host:514
  • to
*.* @@192.168.122.xxx:514
  • where xxx is the IP of vm01 (your logging machine)
  • Now restart your rsyslog service (service rsyslog restart).
  • Go back on to vm01 and edit /etc/rsyslog.conf and make the following change:

change these two lines

#$ModLoad imtcp.so
#$InputTCPServerRun 514
  • to
$ModLoad imtcp.so
$InputTCPServerRun 514
  • Still on vm01, restart syslog. NOTE: At this point you should use iptables to open up tcp port 514 on vm01.
  • Now go back onto f16 and use the logger command to verify logging messages are getting through to vm01. Try this command

logger -p user.warn "Hello World"

  • Use the command "tail /var/log/messages" on vm01 to view the results of the previous step.

Answer the following questions and and email them to your teacher in ASCII text format

  1. What is your full name and 9-digit Seneca student ID?
  2. Show the RSA public key generated on vm01. i.e. the file called id_rsa.pub.
  3. Explain the meaning of the -avz options on the rsync command.
  4. Provide root's cron table on vm01.
  5. What were the last two lines of the email sent to root upon completion of the cron job?
  6. What was the output of 'tail /var/log/messages' at the end of the lab?
  7. What is the output of the iptables-save command on vm01 at the end of this lab?