RedHat EX200 - Red Hat Certified System Administrator - RHCSA (8.2)

echo "1" >/proc/sys/net/ipv4/ip_forward

vi /etc/sysctl.conf

net.ipv4.ip_forward = 1

If you want to use the Linux System as a Router to make communication between different networks, you need enable the IP forwarding. To enable on running session just set value 1 to

/proc/sys/net/ipv4/ip_forward. As well as automatically turn on the IP forwarding features on next boot set on /etc/sysctl.conf file.

groupadd sysmgrs

useradd -G sysmgrs Natasha

We can verify the newly created user by cat /etc/passwd)

# useradd -G sysmgrs harry

# useradd -s /sbin/nologin sarrh

# passwd Natasha

# passwd harry

# passwd sarrah

*

1. Reboot the server pressing by Ctrl+Alt+Del

2. When the boot-loader menu appears, press the cursor keys to highlight the default boot-loader entry

3. Press e to edit the current entry.

4. Use the cursor keys to navigate to the line that starts with linux.

5. Press End to move the cursor to the end of the line.

6. Append rd.break to the end of the line.

7. Press Ctrl+x to boot using the modified configuration.

8. At the switch_root prompt

*

switch_root:/# mount -o remount,rw /sysroot

switch_root:/# chroot /sysroot

sh-4.4# echo kexdrams | passwd --stdin root

Changing password for user root.

passwd: all authentication tokens updated successfully.

sh-4.4# touch /.autorelabel

sh-4.4# exit; exit

*

Type exit twice to continue booting your system as usual.

lvextend -L+200M /dev/test0/testvolume1 Use lvdisplay /dev/test0/testvolume1)

ext2online -d /dev/test0/testvolume1

lvextend command is used the increase the size of Logical Volume. Other command lvresize command also here to resize. And to bring increased size on online we use the ext2online command.

# cd /etc/syscofig/network-scripts/

# ls

# vim ifcfg-eth0 (Configure IP Address, Gateway and DNS) IPADDR=172.24.40.40

GATEWAY=172.24.40.1

DNS1=172.24.40.1

# vim /etc/sysconfig/network

(Configure Host Name)

HOSTNAME= station.domain40.example.com

OR

Graphical Interfaces:

System->Preference->Network Connections (Configure IP Address, Gateway and DNS) Vim /etc/sysconfig/network

(Configure Host Name)

vi /etc/httpd/conf.d/ssl.conf ServerName www.rhce.com DocumentRoot /var/www/rhce DirectoryIndex index.html index.htm ServerAdmin webmaster@rhce.com SSLEngine on SSLCertificateFile /etc/httpd/conf/ssl.crt/server.crt SSLCertificateKeyFile /etc/httpd/conf/ssl.key/server.key

cd /etc/httpd/conf

3 make testcert

Create the directory and index page on specified path. (Index page can download from ftp://server1.example.com at exam time)

service httpd start|restart

chkconfig httpd on

Apache can provide encrypted communications using SSL (Secure Socket Layer). To make use of encrypted communication, a client must request to https protocol, which is uses port 443. For HTTPS protocol required the certificate file and key file.

*

[root@node2 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

vdc 252:32 0 5G 0 disk

└─vdc1 252:33 0 4.1G 0 part

└─datavg-datalv 253:3 0 3.9G 0 lvm /data

vdd 252:48 0 5G 0 disk

vde 252:64 0 10G 0 disk

[root@node2 ~]# swapon -s

Filename Type Size Used Priority

/dev/dm-1 partition 2097148 1548 -2

[root@node2 ~]# free -m

total used free shared buff/cache available

Mem: 1816 1078 104 13 633 573

Swap: 2047 1 2046

[root@node2 ~]# parted /dev/vdc print

Number Start End Size Type File system Flags

1 1049kB 4404MB 4403MB primary lvm

*

[root@node2 ~]# parted /dev/vdc mkpart primary linux-swap 4404MiB 5060MiB

[root@node2 ~]# mkswap /dev/vdc2

Setting up swapspace version 1, size = 656 MiB (687861760 bytes)

no label, UUID=9faf818f-f070-4416-82b2-21a41988a9a7

[root@node2 ~]# swapon -s

Filename Type Size Used Priority

/dev/dm-1 partition 2097148 1804 -2

[root@node2 ~]# swapon /dev/vdc2

*

[root@node2 ~]# swapon -s

Filename Type Size Used Priority

/dev/dm-1 partition 2097148 1804 -2

/dev/vdc2 partition 671740 0 -3

[root@node2 ~]# blkid

/dev/vdc2: UUID="9faf818f-f070-4416-82b2-21a41988a9a7" TYPE="swap" PARTUUID="0f22a35f-02"

[root@node2 ~]# vim /etc/fstab

UUID=9faf818f-f070-4416-82b2-21a41988a9a7 swap swap defaults 0 0

[root@node2 ~]# reboot

[root@node2 ~]# swapon -s

Filename Type Size Used Priority

/dev/dm-1 partition 2097148 1804 -2

/dev/vdc2 partition 671740 0 -3

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

service network restart

Gateway defines the way to exit the packets. According to question System working as a router for two networks have IP Address 192.168.0.254 and 192.168.1.254.

useradd -u 3400 iar

passwd iar

rpm -ivh ftp://server1/example.com/pub/updates/zsh-*

or

Login to ftp server : ftp ftp://server1.example.com using anonymous user.

Change the directory: cd pub and cd updates

Download the package: mget zsh-*

Quit from the ftp prompt : bye

Install the package

rpm -ivh zsh-*

Verify either package is installed or not : rpm -q zsh