Tag: redhat
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rpm verify packages
To verify a package installed on system, you can use
rpm -V PKG_NAME
Example
[root@hello-1 curl-curl-7_69_0]# rpm -V bind S.5....T. c /etc/named.conf [root@hello-1 curl-curl-7_69_0]#
Here bind package have /etc/named.conf file modified.
To verify all packages on system, run
rpm -Va
Back to rpm
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RHCSA Study Guide
1. Logical volume ‘home’ as created and mounted. Reduce its size to ‘192M’ (size from 185M to 200MB is acceptable)
# lvdispaly # umount /dev/vgsrv/home # e2fsck -f /dev/vgsrv/home # resize2fs /dev/vgsrv/home 192M # lvcreduce -L 192M /dev/vgsrv/home # mount /dev/vgsrv/home # lvdisplay # lvdisplay # umount /dev/vgsrv/home # lvextend -L 256M /dev/vgsrv/home # e2fsck -f /dev/vgsrv/home # resize2fs /dev/vgsrv/home 256M # mount /dev/vgsrv/home # lvdisplay
2. Add a group sysmgrs
Add a user Natasha such that user’s secondary group is sysmgrs.
Add a user harry such that user’s secondary group is sysmgrs.
Add a user sarrah, who has no interactive shell, and not belongs to the group sysmgrs.
Set password of Natasha, harry and sarrah to lotawens.
# 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
3. Configure FTP access on your virtual machine to allow permission for anonymous user.
If yum not configured; # cd /etc/yum.repos.d # vim domain70.repo [domain70] baseurl= enabled=1 gpgcheck=0 :wq! # yum clean all # yum update all # yum install vsftpd* # yum install ftp # ftp ip User: anonymous Password:
If logging successfully, do the last steps; If not, the below mentioned files and make changes. # vim /etc/vsftpd/vsftpd.conf # vim /etc/vsftpd/ftpusers # vim /etc/vsftpd/user_list And try again # service vsftpd restart # chkconfig vsftpd on 4. Make a collaborative directory /a/b and set the permission as
Group ownership of /a/b is sysmgrs
The directory should be readable, writable and accessable to members of sysmgrs, but not to any other user. ( it is undershould that root has access to all files and
directories on the system)Files created in /a/b automatically have group ownership set to the group sysmgrs.
# mkdir -p /a/b # chgrp sysmgrs /a/b # chmod 2770 /a/b
5. Copy the file /etc/fstab to /var/tmp. Configure the permissions of /var/tmp/fstab so that,
The file /var/tmp/fstab is owned by the root user
The file /var/tmp/fstab is belongs to group root
The file /var/tmp/fstab is should not be executable by anyone
The user natasha is able to read and write /var/tmp/fstab
The user harry can neigher write not read /var/tmp/fstab
All other users (current or future) have the ability to read /var/tmp/fstab
# cp -a /etc/fstab /var/tmp # cd /var/tmp # ls -l # getfacl /var/tmp/fstab # chmod ugo-x /var/tmp/fstab [ No need to do this, there won't be execute permission for the file by default] # setfacl -m u:natasha:rw /var/tmp/fstab # setfacl -m u:harry:0 /var/tmp/fstab (zero) [Read permission will be there for all the users, by default. Check it using ls -l /var/tmp/fstab] Verify by [ ls -la /var/tmp/fstab]
6. set cronjob for user natasha to do /bin/echo hiya at 14:23
# crontab -e -u natasha 23 14 * * * /bin/echo hiya :wq!
7. host.domain70.example.com shares remote users. Configure ldap such that ldapusers has no home directory until we do automounting.
baseDN: dc=domain70, dc=example, dc=com
Certificate: ftp://host.domain70.example.com/pub/EXAMPLE-CA-CERT
Username: ldapuser70
Password: password
# system-config-authentication LDAP user DN=dc=domain70,dc=example,dc=com Server=host.domain70.example.com Certificate= ftp://host.domain70.example.com/pub/exam-crt ( enter url carefully, there maybe // or ..) LDAP password OK starting sssd # su -ldapuser70 Display Bash prompt #exit
8. configure NTP with that of rhcert.domain70.example.com
# system-config-date Delete old server names and add given server name Advanced Tick speedup #exit
9. Implement a web server for the site http://station.domain70.example.com/ then perform the following steps:
Download ftp://rhcert.domain70.example.com/pub/rhcsa/station.html
Rename the download file to index.html
Copy this index.html to the Document root of your web server.
DO NOT make any modifications to the content of index.html
# yum install httpd # cd /var/www/html # wget ftp://rhcert.domain70.example.com/pub/rhcsa/station.html # mv station.html index.html 990th line : remove '#' Remove '*' and add IP address: Eg Name VirtualHost 172.40.70.12 1003rd line copy 7 lines and paste below that itself. (last 7 lines) Remove # of all lines Ist line : remove * and add ip
3rd line Document Root /var/www/html 4th line server name station.domain70.example.com :wq! #service httpd restart # chkconfig httpd on check site http://station.domain70.example.com/ 10. Install the appropriate Kernel update from ftp://domain70.example.com/pub/updates/ The following criteria must also be met:
The updated kernel is the default Kernel when the system is rebooted.
The orginal kernel remains available and bootable on the system.
# ftp rhcert.domain70.example.com Anonymous login ftp> cd /pub/updates ftp> ls ftp> mget kernel* ftp> bye # rpm -ivh kernel* # vim /etc/grub.conf Check the updatted kernel is the first kernel and the orginal kernel remains available. set default=0 :wq!
11. Configure autofs to automount the home directories of ldapusers host.domain70.example.com NFS-exports /rhome to your
machine. ldapuser70’s home directory should be automounted locally beneath /rhome/ldapuser7-. Home directores must be writable by thier users.User: ldpauser70
Password: password# vim /etc/auto.master /rhome /etc/auto.misc :wq! # vim /etc/auto.misc ldapuser70 --rw,sync host.domain70.example.com:/rhome/ldpauser70 :wq! #service autofs restart # service autofs reload # chkconfig autofs on # su -ldapuser70 Login ldapuser with home directory # exit
12. Create a swap partition of 754 MB size. Do not make any change to the existing swap partition
# fdisk -l # fdisk -cu /dev/vda p n e or p select e default (first): enter default (last): enter n default(first): enter default(first): +754M t(1-5) l: 82 p w #reboot #mkswap /dev/vda5 # vim /etc/fstab /dev/vda5 swap swap defaults 0 0 :wq # mount -a # swapon -a # swapon -s
13. Add a user manlo with uid 1353. Set his password as lotawens
# useradd -u 1353 manlo # passwd manlo # su - manlo
14. Locate all files and directories of user jacques and copy it to /root/findfiles
OR locate the files of owner “dax” and copy to the directory /root/founddirectory
OR Find files in your system which is owned by andrew user & save on /backup/somefile.
# find / -user jacques > /root/findfiles ( if /root/findfiles is a file) # mkdir -p /root/findfiles # find / -user jacques -exec cp -a {} /root/findfiles\; [ if /root/findfiles is a directory ]
15. Find all lines contain a string loop in a file /etc/grub.conf copy it to /root/list. Don’t leave a free line in /root/list
grep loop /etc/hosts > /root/list
16. Create a device:
Logical volume qa with 60 extents.
Volume group qagroup with 16MB extent size.
Mount it permanently under /abc with file system ext3
# fdisk -l # fdisk -cu /dev/vda n default(first) default(last): +1000M (since 60 extents of 16M = 16*60=960MB lvm; So physical volume > 960MB) t(1-6):6 l:8e p w # reboot(init6) # pvcreate /dev/vda6 # vgcreate -s 16M qagroup /dev/vda6 # lvcreate -l 60 -n qa qagroup # mkfs.ext3 /dev/qagroup/qa # mkdir /abc # vim /etc/fstab /dev/qagroup/qa /abc ext3 defaults 0 0 :wq # mount -a