EX200 無料問題集「RedHat Red Hat Certified System Administrator - RHCSA」
Configure NTP.
Configure NTP service, Synchronize the server time, NTP server: classroom.example.com
Configure NTP service, Synchronize the server time, NTP server: classroom.example.com
正解：
Configure the client:
Yum -y install chrony
Vim /etc/chrony.conf
Add: server classroom.example.com iburst
Start: systemctl enable chronyd
systemctl restart chronyd
Validate: timedatectl status
Yum -y install chrony
Vim /etc/chrony.conf
Add: server classroom.example.com iburst
Start: systemctl enable chronyd
systemctl restart chronyd
Validate: timedatectl status
Create a 2G swap partition which take effect automatically at boot-start, and it should not affect the original swap partition.
正解：
# fdisk /dev/sda
p
(check Partition table)
n
(create new partition: press e to create extended partition, press p to create the main partition, and the extended partition is further divided into logical partitions) Enter
+2G
t
l
W
partx -a /dev/sda
partprobe
mkswap /dev/sda8
Copy UUID
swapon -a
vim /etc/fstab
UUID=XXXXX swap swap defaults 0 0
(swapon -s)
p
(check Partition table)
n
(create new partition: press e to create extended partition, press p to create the main partition, and the extended partition is further divided into logical partitions) Enter
+2G
t
l
W
partx -a /dev/sda
partprobe
mkswap /dev/sda8
Copy UUID
swapon -a
vim /etc/fstab
UUID=XXXXX swap swap defaults 0 0
(swapon -s)
We are working on /data initially the size is 2GB. The /dev/test0/lvtestvolume is mount on /dat a. Now you required more space on /data but you already added all disks belong to physical volume. You saw that you have unallocated space around 5 GB on your harddisk. Increase the size of lvtestvolume by 5GB.
正解：
Create a partition having size 5 GB and change the syste id '8e'.
use partprobe command
pvcreate /dev/hda9 Suppose your partition number is hda9.
vgextend test0 /dev/hda9 vgextend command add the physical disk on volume group.
lvextend -L+5120M /dev/test0/lvtestvolume
verify using lvdisplay /dev/test0/lvtestvolume.
use partprobe command
pvcreate /dev/hda9 Suppose your partition number is hda9.
vgextend test0 /dev/hda9 vgextend command add the physical disk on volume group.
lvextend -L+5120M /dev/test0/lvtestvolume
verify using lvdisplay /dev/test0/lvtestvolume.
You are a System administrator. Using Log files very easy to monitor the system. Now there are 50 servers running as Mail, Web, Proxy, DNS services etc. You want to centralize the logs from all servers into on LOG Server. How will you configure the LOG Server to accept logs from remote host?
正解：
By default, system accept the logs only generated from local host. To accept the Log from other host configure:
vi /etc/sysconfig/syslog SYSLOGD_OPTIONS="-m 0 -r"
Where
-m 0 disables 'MARK' messages.
-r enables logging from remote machines
-x disables DNS lookups on messages received with -r
service syslog restart
vi /etc/sysconfig/syslog SYSLOGD_OPTIONS="-m 0 -r"
Where
-m 0 disables 'MARK' messages.
-r enables logging from remote machines
-x disables DNS lookups on messages received with -r
service syslog restart
Part 2 (on Node2 Server)
Task 6 [Implementing Advanced Storage Features]
Add a new disk to your virtual machine with a ize of 10 GiB
On this disk, create a VDO volume with a size of 50 GiB and mount it persistently on /vbread with xfs filesystem
Task 6 [Implementing Advanced Storage Features]
Add a new disk to your virtual machine with a ize of 10 GiB
On this disk, create a VDO volume with a size of 50 GiB and mount it persistently on /vbread with xfs filesystem
正解：
* [root@node2 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
vdd 252:48 0 5G 0 disk
vde 252:64 0 10G 0 disk
[root@node2 ~]# yum install kmod-kvdo vdo
[root@node2 ~]# systemctl enable --now vdo
[root@node2 ~]# systemctl start vdo
[root@node2 ~]# systemctl status vdo
[root@node2 ~]# vdo create --name=vdo1 --device=/dev/vde --vdoLogicalSize=50G
[root@node2 ~]# vdostats --hu
Device Size Used Available Use% Space saving%
/dev/mapper/vdo1 10.0G 4.0G 6.0G 40% N/A
[root@node2 ~]# mkfs.xfs -K /dev/mapper/vdo1
* [root@node2 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
vde 252:64 0 10G 0 disk
└─vdo1 253:4 0 50G 0 vdo
[root@node2 ~]# mkdir /vbread
[root@node2 ~]# blkid
/dev/mapper/vdo1: UUID="1ec7a341-6051-4aed-8a2c-4d2d61833227" BLOCK_SIZE="4096" TYPE="xfs"
[root@node2 ~]# vim /etc/fstab
UUID=1ec7a341-6051-4aed-8a2c-4d2d61833227 /vbread xfs defaults,x-systemd.requires=vdo.service 0 0
[root@node2 ~]# mount /dev/mapper/vdo1 /vbread/
[root@node2 ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/vdo1 xfs 50G 390M 50G 1% /vbread
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
vdd 252:48 0 5G 0 disk
vde 252:64 0 10G 0 disk
[root@node2 ~]# yum install kmod-kvdo vdo
[root@node2 ~]# systemctl enable --now vdo
[root@node2 ~]# systemctl start vdo
[root@node2 ~]# systemctl status vdo
[root@node2 ~]# vdo create --name=vdo1 --device=/dev/vde --vdoLogicalSize=50G
[root@node2 ~]# vdostats --hu
Device Size Used Available Use% Space saving%
/dev/mapper/vdo1 10.0G 4.0G 6.0G 40% N/A
[root@node2 ~]# mkfs.xfs -K /dev/mapper/vdo1
* [root@node2 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
vde 252:64 0 10G 0 disk
└─vdo1 253:4 0 50G 0 vdo
[root@node2 ~]# mkdir /vbread
[root@node2 ~]# blkid
/dev/mapper/vdo1: UUID="1ec7a341-6051-4aed-8a2c-4d2d61833227" BLOCK_SIZE="4096" TYPE="xfs"
[root@node2 ~]# vim /etc/fstab
UUID=1ec7a341-6051-4aed-8a2c-4d2d61833227 /vbread xfs defaults,x-systemd.requires=vdo.service 0 0
[root@node2 ~]# mount /dev/mapper/vdo1 /vbread/
[root@node2 ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/vdo1 xfs 50G 390M 50G 1% /vbread
Part 1 (on Node1 Server)
Task 13 [Archiving and Transferring Files & SELinux]
Create a backup file named /root/backup.tar.bz2. The backup file should contain the content of /usr/local and should be zipped with bzip2 compression format.
Furthermore, ensure SELinux is in enforcing mode. If it is not, change SELinux to enforcing mode.
Task 13 [Archiving and Transferring Files & SELinux]
Create a backup file named /root/backup.tar.bz2. The backup file should contain the content of /usr/local and should be zipped with bzip2 compression format.
Furthermore, ensure SELinux is in enforcing mode. If it is not, change SELinux to enforcing mode.
正解：
* [root@node1 ~]# tar cvf /root/backup.tar /usr/local/
tar: Removing leading `/' from member names
/usr/local/
/usr/local/bin/
/usr/local/etc/
[root@node1 ~]# ls
backup.tar
[root@node1 ~]# file backup.tar
backup.tar: POSIX tar archive (GNU)
[root@node1 ~]# bzip2 backup.tar
[root@node1 ~]# ls
backup.tar.bz2
[root@node1 ~]# file backup.tar.bz2
backup.tar.bz2: bzip2 compressed data, block size = 900k
*
[root@node1 ~]# sestatus
SELinux status: enabled
[root@node1 ~]# cat /etc/selinux/config
SELINUX=enforcing
SELINUXTYPE=targeted
[root@node1 ~]# reboot
### For Checking ###
[root@node1 ~]# sestatus
SELinux status: enabled
tar: Removing leading `/' from member names
/usr/local/
/usr/local/bin/
/usr/local/etc/
[root@node1 ~]# ls
backup.tar
[root@node1 ~]# file backup.tar
backup.tar: POSIX tar archive (GNU)
[root@node1 ~]# bzip2 backup.tar
[root@node1 ~]# ls
backup.tar.bz2
[root@node1 ~]# file backup.tar.bz2
backup.tar.bz2: bzip2 compressed data, block size = 900k
*
[root@node1 ~]# sestatus
SELinux status: enabled
[root@node1 ~]# cat /etc/selinux/config
SELINUX=enforcing
SELINUXTYPE=targeted
[root@node1 ~]# reboot
### For Checking ###
[root@node1 ~]# sestatus
SELinux status: enabled
Please open the ip_forward, and take effect permanently.
正解：
vim /etc/sysctl.conf net.ipv4.ip_forward = 1
sysctl -w (takes effect immediately)
If no "sysctl.conf" option, use these commands:
sysctl -a |grep net.ipv4
sysctl -P net.ipv4.ip_forward = 1
sysctl -w
sysctl -w (takes effect immediately)
If no "sysctl.conf" option, use these commands:
sysctl -a |grep net.ipv4
sysctl -P net.ipv4.ip_forward = 1
sysctl -w
Create the following users, groups, and group memberships:
A group named adminuser.
A user natasha who belongs to adminuser as a secondary group A user harry who also belongs to adminuser as a secondary group.
A user sarah who does not have access to an interactive shell on the system, and who is not a member of adminuser, natasha, harry, and sarah should all have the password of redhat.
A group named adminuser.
A user natasha who belongs to adminuser as a secondary group A user harry who also belongs to adminuser as a secondary group.
A user sarah who does not have access to an interactive shell on the system, and who is not a member of adminuser, natasha, harry, and sarah should all have the password of redhat.
正解：
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
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
Add a swap partition.
Adding an extra 500M swap partition to your system, this swap partition should mount automatically when the system starts up. Don't remove and modify the existing swap partitions on your system.
Adding an extra 500M swap partition to your system, this swap partition should mount automatically when the system starts up. Don't remove and modify the existing swap partitions on your system.
正解：
fdisk -cu /dev/vda// in the way of expanding the partition, don't make main partition partx -a /dev/vda mkswap /dev/vdax swapon /dev/vdax swapon -s vi /etc/fstab
/dev/vdaxswapswapdefaults0 0
mount -a
/dev/vdaxswapswapdefaults0 0
mount -a