How to Easily Pass the RedHat RH302 Exam: Expert Advice

Do the following steps as:

1.vi /etc/httpd/conf/httpd.conf

<VirtualHost 192.100.0.1>

ServerNamewww.abc.com

DocumentRoot /var/www/abc/

<Directory /var/www/abc>

Order Allow, Deny

Allow from .example.com

</Directory>

DirectoryIndexindex.html

ServerAdminwebmaster@abc.com

ErrorLog logs/error_abc.logs

CustomLog logs/custom_abc.logs common

</VirtualHost>

2.Create the directory and index page on specified path. (Index page can download fromftp://server1.example.comat exam time)

3.service httpd start|restart

4.chkconfig httpd on

Order allow, denyAllows explicitly allowed clients, denies everyone else; clients matched by both allow and deny are denied.

Order deny, allowdenies explicitly denied clients, allows everyone else, clients matched by both allow and deny are allowed.

Do the following steps as:

1.vi /etc/squid/squid.conf

#detault:

http_port8080

#Recommended minimum configuration:

# Near the src acl src section

acl allownet src 192.168.0.0/255.255.255.0

acl denynet src 192.168.1.0/255.255.255.0

#Default:

# http_access deny all

#Under Herehttp_access allow allownet

http_access deny denynet

2.service squid start

3.chkconfig squid on

squid is a proxy caching server, using squid we can share the internet, block the internet, to certain network. First we should define the port for squid, the standard port for squid is 3128. We can run squid on different port by specifying http_port portnumber.

To block or allow the Internet access to hosts, we should create the acl (Access Control List). In this file we can specify only the IP address.

Example: acl aclname src IP/NetmaskAfter creating acl we can block or allow the internet to specified acl.

http_access allow | deny alcname

Do the following steps as:

1.vi /etc/mail/local-host-names

example.com

2.vi /etc/mail/sendmail.mc

dnl # DEAMON_OPTIONS(`Port=smtp,Addr=127.0.0.1,Name=MTA`)dnl

3.m4 /etc/mail/sendmail.mc >/etc/mail/sendmail.cf

4.vi /etc/mail/access

example.comRELAY

RELAY

5.service sendmail start | restart

6.chkconfig sendmail on

/etc/mail/local-host-names file contains the aliases to hostname. Mail server program reads the /etc/mail/sendmail.cf. To change the configuration on mail server, we should edit the /etc/mail/sendmail.mc file and should generate the sendmail.cf using m4 command.

By default sendmail server allows to connect to local host only. So we should edit the /etc/mail/sendmail.mc file to allow connect to other hosts.

By default sendmail server will not forward mail. we should specify on /etc/mail/access to relay or to block mail coming from domain or network or individual email address.

Do the following steps as:

1.vi /etc/exports

/local*.example.com(rw,sync) trusted.cracker.org(ro,sync)

service nfs start | restart

service portmap start | restart

chkconfig nfs on

chkconfig portmap on

In Linux to share the data we use the /etc/exports file. Pattern is:

Pathclient(permission)

Shared Directory Path, Client can be single host or domain name or ip address. Permission should specify without space with client lists in parentheses. NFS is RPC service so portmapper service should restart after starting the nfs service. We can specify multiple clients’ list separating by space with different shared option.

Do the following steps as:

1.vi /etc/mail/local-host-names

example.com

2.vi /etc/mail/sendmail.mc

dnl # DEAMON_OPTIONS(`Port=smtp,Addr=127.0.0.1,Name=MTA`)dnl

3.m4 /etc/mail/sendmail.mc >/etc/mail/sendmail.cf

4.vi /etc/mail/access

192.168.0RELAY

@cracker.orgREJECT

5.service sendmail start | restart

6.chkconfig dovecot on

7.vi /etc/dovecot.conf

protocols = pop3 pop3s imap imaps

8.service dovecot start | restart

9.chkconfig dovecot on

10.vi /etc/aliases

user5:user2

11.newaliases

/etc/mail/local-host-names file contains the aliases to hostname. Mail server program reads the /etc/mail/sendmail.cf. To change the configuration on mail server, we should edit the /etc/mail/sendmail.mc file and should generate the sendmail.cf using m4 command.

By default sendmail server allows to connect to local host only. So we should edit the /etc/mail/sendmail.mc file to allow connect to other hosts.

By default sendmail server will not forward mail. we should specify on /etc/mail/access to relay or to block mail coming from domain or network or individual email address.

By default dovecot service start only the imap protocol. To start pop protocol with dovecot, we should write in /etc/dovecot.conf file.

Using /etc/aliases file we can map the user name to send mail of one user to another user. To rebuild database we use the newaliases command.

After completing the Boot loader problem, you will boot the system, but it goes to emergency mode. Remember that if System boots on Emergency mode that means file system problem.

You will get the Shell, remount the / filesystem with read and write mode.

1.First Find out the / filesystem using e2lable /dev/hda1, e2lable /dev/hda2 etc

2.mount –o remount,defaults /dev/hda? /

3.vi /etc/fstab

You will get like:

/root/ext3defaults 1 1

or //rootext3defaults 1 1

4.Edit the file like:

//ext3defaults 1 1

5.Configure the /etc/grub.conf file if just booting system by editing grub from grub prompt.

6.Reboot the system.

This is boot related problem. There will be same questions repeated two times but problem is different.

First When you restart the system you will get the Error:

File Not Found

mount: error 15 mounting ext3

mount: error 2 mounting none

switchroot: mount failed: 22

umount /initrd/dev/: 2

Kernel Panic: no syncing: Attempted to kill init !

Restart the System

Check the grub boot loader configuration by pressing e shortcut key.

You will see like:

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root= / rhgb quiet

initrd /initrd-2.6.9-5.EL.img

OR

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/root rhgb quiet

initrd /initrd-2.6.9-5.EL.img

Then Edit Boot loader to make like

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet

initrd /initrd-2.6.9-5.EL.img

Check all lines and edit as same as above. Press b to boot the system

After booting the system you should correct the /etc/grub.conf file.

If still you are getting Error likeFile not found, it seems that either kernel file or initrd file is missing. To troubleshoot with these problem, boot the system on rescue mode.

linux rescue

chroot /mnt/sysimage

Check the files on /boot, if not available install the kernel package from ftp or nfs server

Create the initrd image file on boot using: mkinitrd initrd-2.6.9-5.EL.img `uname –r`

This is boot related problem. There will be same questions repeated two times but problem is different.

First When you restart the system you will get the Error:

mount: error 15 mounting ext3

mount: error 2 mounting none

switchroot: mount failed: 22

umount /initrd/dev/: 2

Kernel Panic: no syncing: Attempted to kill init !

This error occurred in your system before showing welcome redhat linux. That means problem in grub boot loader.

Restart the System

Check the grub boot loader configuration by pressing e shortcut key.

You will see like:

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root= / rhgb quiet

initrd /initrd-2.6.9-5.EL.img

OR

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/root rhgb quiet

initrd /initrd-2.6.9-5.EL.img

Then Edit Boot loader to make like

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet

initrd /initrd-2.6.9-5.EL.img

Check all lines and edit as same as above. Press b to boot the system

After booting the system you should correct the /etc/grub.conf file.

Do the following steps as:

vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0

BOOTPROTO=static

ONBOOT=yes

IPADDR=x.x.x.x

NETMASK=x.x.x.x

Enter the IP Address as given station number by your examiner: example: 172.24.0.1

Enter Subnet Mask

Enter Default Gateway and primary name server

press on ok

ifdown eth0

ifup eth0

verify using ifconfig

In the lab server is playing the role of router, IP forwarding is enabled. Just set the Correct IP and gateway, you can ping to 172.25.254.254.

Do the following steps as:

hostname station?.example.comThis will set the host name only for current session. To set hostname permanently.

vi /etc/sysconfig/network

HOSTNAME=station?.example.com

service network restart