Rhcsa Exam Model Question

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RHCSA EXAM MODEL QUESTION

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To Display Exam Question

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Crack root password

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Set hostname

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Set IP Address

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yum repo

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Cracking root password

use ctl+alt+del in send keys tab in virtual server m/c

when grub displays press tab key to freeze .Press e to edit grub

search for Linux16 string and press end key and add this line

rd.break console=tty

press ctl+x to save and restart

#root: mount -o remount,rw /sysroot

#chroot /sysroot/

sh] passwd

new password: confirm password: sh] touch /autorelabel exit exit

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Setting hostname

#hostname (or) #cat /etc/hostname displays the current hostname Change host temporarily #host newhostname change host permanently

#hostctl set-hostname newhostname

Setting hostname using nmtui

#nmtui

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Setting IP Address

Setting IP

Can be in 3 ways

● Network Manager (GUI) ● nmcli

● nmtui

Using Network Manager

Go to right top where network manager icon and set ip,dns and gateway address from the question Using nmtui

#nmtui

Set the values for ip,dns,gateway

Using nmcli

#nmcli device status adding connection

#nmcli connection.add con-name as ifname etho type ethernet ip4 172.25.7.0 gw4 172.25.0.0 set dns

#nmcli connection modify as ip4.dns 172.25.6.8 manual assign

#nmcli connection modify as ip4.method manual Set auto connect

#nmcli connection modify as connection. autoconnect yes

Activate connection

#nmcli connection up con-name Restart network

#systemctl restart network To check

#ifconfig

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Setting yum repo and SElinux

Setting yum repo

#cd /etc/yum.repos.d/ #vim myown.repo [myown]

baseurl=”paste the url from the question” enabled=1

gpgcheck=0 :wq

#yum clean all #yum repolist all

#yum install any package to check if its installing from our own repo

Set SELinux Permission #vim /etc/sysconfig/selinux

change the line selinux=premissive to

selinux=enforcing :wq

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1 . swap partition

#fdisk -l

#fdisk /dev/vda

P - print the list of pratitions

n - create new partition

e or p (extended or primary)

:e

default(first sector)

default(last sector)

: n

default(first sector)

default(last sector) +100M

t

l: 82 ( linux swap type)

:p (to print the partitions)

:w (to save the changes)

#partprobe (intimate to kernel)

#mkswap /dev/vda2

#mkdir /test

#vim /etc/fstab

/dev/vda2 /test swap swap defaults 0 0

#swapon -a

#mount -a

#df -h

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2 . user, group creation with permissions

User creation with UID

#useradd -u 2323 ashwin

#passwd ashwin

#cat /etc/passwd

User creation with no login shell

#useradd -s /bin/nologin kaviya

#passwd kaviya

#su - kayiva

Not allowed

# date -d “+1month”

# usermod -e YYYY-MM-DD ashwin

or # chage -E YYYY-MM-DD ashwin

# chage -l ashwin

Group creation and adding user

#groudadd sysmanager

#chgrp sysmanager ashwin

Adding to user when creating user

#useradd -G sysmanager ashwin

Setting permission for file or folder

#chmod u-x,g-x,o-x /file or /folder

removes execute permission to all

#setfacl -m u:ashwin: 0 /file or /folder/

removes read/write for user ashwin

#chmod g+rwx,o= /file or folder

others dont have permission to read,write

#chmod g+s /file or folder

files will be created in group ownership

automatically

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3 . Crontab

Set cronjon for user to /bin/echo string at h:m

#crontab -e -u username

**m h * * * /bin/echo "string"**

#systemctl restart crond.service

#su - username

#mail

Deny Cron for specific user

#vim /etc/cron.deny

ashwin

#crontab -e -u ashwin

This program is not allowed

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4 . find grep copy command combined & collaborative directory

Locate files of user and copy to to some path #find / -user ashwin -exec cp -a {}/file path \; Note: If path doesnt exists create using mkdir Find string in all file and copy to some path #grep "string" /source > /destination path

Creating Collaborative directory #mkdir -p /a/b

#chgrp sysmanager /a/b #chmod g+rw,o= /a/b or

#chmod 770 /a/b

sets read,write to group sysmanger and other no permission to access /a/b

#chmod g+s /a/b

sets group permission automatically when files created in that directory

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5 . LDAP

Setting LDAP

#yum install authconfig-gtk* ssd* krb5* -y

#authconfig-gtk

Set all the values from question

#getent passwd ldauserx( x denotes station

number)

You can see details about ldapuserx

Autofs

#yum install autofs* -y #systemctl restart autofs #systemctl enable autofs #vim /etc/auto.master /rhome /etc/auto.misc #vim /etc/auto.misc

ldapuserx -rw,sync,nfvers=3 servername:/rhome/ldapuserx #systemctl restart autofs

#systemctl enable autofs

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LVM reduce #lvdisplay #vim /etc/fstab #umount /dev/vgname/vo #e2fsck -f /dev/vgname/vo #resize2fs -p* /dev/vgname/vo 120M #lvreduce -L 120M /dev/vgname/vo #mount /dev/vgname #lvdisplay #df -h LVM Increase #lvdisplay #vim /etc/fstab #umount /dev/vgname #e2fsck -f /dev/vgname #lvextend -L 120M /dev/vgname #resize2fs -p /dev/ #mount /dev/vgname #lvdisplay #df -h

6 . LVM

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7 . LVM creation

#fdisk -l

#fdisk /dev/vda

P - print the list of pratitions

n - create new partition

e or p (extended or primary)

:e

default(first sector)

default(last sector)

: n

default(first sector)

default(last sector) +100M

t

l: 83 ( linux LVM type)

:p (to print the partitions)

:w (to save the changes)

#partprobe (intimate to kernel)

Creating physical volume #pvcreate /dev/vdb4 Creating volume group

#vgcreate -s 8M vgname /dev/vdb4 Creating volume

#lvcreate -l 35 -n volname /dev/mapper/vgname Display volume #lvdisplay

Create directory to mount #mkdir /lvm

Convert volume to filesystem #mkfs.ext3 /dev/mapper/vgnanme/volna me #mkfs.vfat /dev/mapper/vgname/volnam e