Skip to content

Latest commit

 

History

History
154 lines (126 loc) · 3.7 KB

RHEL7.md

File metadata and controls

154 lines (126 loc) · 3.7 KB

Red Hat Enterprise Linux Server release 7.2 (Maipo) (HVM)

Security

Firewall Disable

If needed stop firewall (not enabled or available)

systemctl status firewalld
service firewalld stop
systemctl disable firewalld

Firewall Open specific ports

firewall-cmd --zone=public --add-port=80/tcp --permanent

Disable SELinux

sed 's/enforcing/disabled/g' -i /etc/sysconfig/selinux
sed 's/enforcing/disabled/g' -i /etc/selinux/config

Disable Services

sudo systemctl stop postfix
sudo systemctl disable postfix

Create new user

useradd -c "Product specific user" -d /home/demo -g users -m -N demo

Add the new user demo to /etc/sudoers to give sudo privilege without password for all commands.

demo ALL=(ALL) NOPASSWD:ALL

Configuration

Timezone

timedatectl set-timezone America/New_York

Setup Disk

Setup new disk as physical volume

> fdisk /dev/xvdb`
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier ------

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
Select (default p): p
Partition number (1-4): 1
First cylinder (1-6527, default 1): 1
Last cylinder, +cylinders or +size{K,M,G} (1-6527, default 6527): [Enter]
Using default value 6527
Partition 1 of type Linux and of size 50 GiB is set

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

Format the new volume created

> mkfs.ext4 -L Product /dev/xvdb1
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=Product
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
3276800 inodes, 13106944 blocks
655347 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2162163712
400 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks: 
	32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 
	4096000, 7962624, 11239424

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

Create a new directory and mount formatted volume

mkdir /opt/product
mount -t ext4 /dev/xvdb1 /opt/product/
chown demo:users /opt/product/

Configure to automatic mount new file system

Add the new disk in mount file /etc/fstab
/dev/xvdb1 /opt/product ext4 defaults 0 2

Swap file setup

Create swap file

mkdir /opt/swap
cd /opt/swap
dd if=/dev/zero of=/opt/swap/swapfile bs=1024 count=2MB

Format swap file

mkswap /opt/swap/swapfile

Configure to automatic mount new swap file

cp /etc/fstab /etc/fstab.bak
echo "/opt/swap/swapfile          swap            swap    defaults        0 0" >>/etc/fstab`

Change hostname

  1. Add preserve_hostname: true at end of the /etc/cloud/cloud.cfg file on your RHEL 7 or Centos 7 Linux instance to ensure that hostname is preserved after reboot.
  2. Run the following command to set the new name.
hostnamectl set-hostname <new host name>.demo.ap

Add the new name to /etc/hosts file to ensure that it is resolved correctly.

Update

Update the install

yum update

DHCP Configuration

Override DNS Configuration provided as part of DHCP. Add the following entry to /etc/dhcp/dhclient.conf file

supersede domain-name-servers 8.8.8.8;