Pass the RedHat RHCE RH302 Questions and answers with ExamsMirror

Do the following steps as:

1.vi /etc/security/limits.conf

user1hardnproc7

2.vi /etc/pam.d/system-auth

sessionrequired/lib/security/pam_limits.so

To limit the number of process or number of logins, we should configure on /etc/security/limits.conf. First Columns contains the username separated by comma or @group name. Second column either hard or soft limits. Third columns called the item, maxloigns or nproc etc.

To identify the session of users we should call the pam_limits module in /etc/pam.d/system-auth.

Do the following steps as:

ftpftp.server1.example.com

Download thewww.html

move the downloaded file into /var/www/html

Rename the file into index.html

Check using linkshttp://stationx.example.com

/var/www/html is the default directory for httpd service. Index.html is the default directory index. To set the default page without configuring virtualhost copy the file as a index.html in /var/www/html.

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 msnnet dstdomain .msn.com

#Default:

# http_access deny all

#Under Herehttp_access deny msnnet

http_access allow allownet

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/samba/smb.conf

[global]

netbios name=station?

workgroup = mygroup

server string=Share from Linux Server

security=user

smb passwd file=/etc/samba/smbpasswd

encrypt passwords=yes

[data]

path=/data

writable=yes

public=no

browsable=yes

valid users=user1 user2

2.smbpasswd –a user1

3.smbpasswd –a user2

4.service smb start | restart

5.chkconfig smb on

Samba servers helps to share the data between linux and windows. Configuration file is /etc/samba/smb.conf. There are some pre-defined section, i. globaluse to define the global options, ii. Printersuse to share the printers, iii. homesuse the share the user’s home directory.

Security=uservalidation by samba username and password. May be there are other users also. To allow certain share to certain user we should use valid users option.

smbpasswdHelps to change user’s smb password. –a option specifies that the username following should be added to the local smbpasswd file.

Do the following steps as:

1.vi /etc/hosts.deny

ALL:.cracker.org EXCEPT trusted.cracker.org

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

-Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

1.vi /etc/exports

/data*.example.com(rw,sync)

2.service nfs start

3.service portmap restart

4.chkconfig nfs on

5.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.

Do the following steps as:

1.vi /etc/security/access.conf

-:jack:ALL EXCEPT station10.example.com

2.vi /etc/pam.d/system-auth

accountrequired/lib/security/pam_access.so

/etc/security/access.conf file helps to allow or deny login to users on the basis of origin.

Syntax of /etc/security/access.conf

permission : users : origins

The first field should be a "+" (access granted) or "-" (access denied) character.

The second field should be a list of one or more login names, group names, or ALL (always matches). A pattern of the form user@host is matched when the login name matches the "user" part, and when the "host" part matches the local machine name.

The third field should be a list of one or more tty names (for non-networked logins), host names, domain names (begin with "."), host addresses, internet network numbers (end with "."), ALL (always matches) or LOCAL (matches any string that does not contain a "." character).

The EXCEPT operator makes it possible to write very compact rules

Do the following steps as:

1.vi /etc/sysconfig/network

GATEWAY=192.168.0.254

OR

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

DEVICE=eth0

BOOTPROTO=static

ONBOOT=yes

IPADDR=192.168.0.?

NETMASK=255.255.255.0

GATEWAY=192.168.0.254

2.service network restart

To automatically mount at boot time we use the /etc/fstab file. Because /etc/rc.d/rc.sysinit file reads and mount all file system specified in /etc/fstab. To mount Network Sharing Files also use the /etc/fstab but filesystem is nfs.

vi /etc/fstab

192.168.0.254:/data/commonnfsdefaults0 0

reboot the system.

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.