Add public IPv4 and IPv6 addresses to a Dedicated Server (Rocky Linux 8 and AlmaLinux 8)

For Dedicated Servers which are managed in the Cloud Panel

This article explains how to add additional public IPv4 and IPv6 addresses to a Dedicated Server with Rocky Linux 8 or AlmaLinux 8 installed.

Note

Instructions on how to establish an encrypted connection to your server are listed in the following articles:

Establishing an SSH connection to your Linux server on a computer with Microsoft Windows

Establishing an SSH connection to your Linux server on a Linux computer

How to configure additional public IPv4 and IPv6 addresses in Rocky Linux 8 and AlmaLinux 8:

Requirements

You have assigned one or more additional public IPv4 and/or IPv6 addresses to your server in the Cloud Panel.
You have logged in to the server as an administrator.
You have noted the IPv4 addresses and IPv6 addresses of the server.

Determine network interface

Determine the file name of the network interface. To do this, enter the following command:

[root@localhost ~]# ip addr

In the following example, the network interface eth0 is used:

[root@7969D9F ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether a8:a1:59:c0:87:4c brd ff:ff:ff:ff:ff:ff:ff
altname enp35s0
inet 217.160.44.181/32 scope global dynamic noprefixroute eth0
valid_lft 39587sec preferred_lft 39587sec
inet6 2001:8d8:1800:832d::1/128 scope global dynamic noprefixroute
valid_lft 3449sec preferred_lft 3449sec
inet6 fe80::4ae7:2b6c:61da:4c5a/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: eth1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
link/ether a8:a1:59:c0:87:4d brd ff:ff:ff:ff:ff:ff:ff
altname enp36s0
4: usb0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000
link/ether 6a:79:e7:f6:66:64 brd ff:ff:ff:ff:ff:ff:ff
altname enp3s0f0u14u3c2

Show DNS server

To display the DNS servers used, enter the following command:
[root@localhost ~]# cat /etc/resolv.conf
The DNS servers used are then displayed in the nameserver entry. Example:
[root@localhost ~]# cat /etc/resolv.conf
# Generated by NetworkManager
nameserver 212.227.123.16
nameserver 212.227.123.17
Make a note of the DNS servers.

Display gateway for IPv4 and IPv6

To display the default gateway of the active interface, enter the following commands:

IPv4:

[root@localhost ~]# ip route show | grep 'default'

IPv6:

[root@localhost ~]# ip -6 route show | grep 'default'

[root@localhost ~]# ip -6 route show default

Add IPv4 and IPv6 addresses

Open the file /etc/sysconfig/network-scripts/ifcfg-eth0 with the vi editor.
[root@localhost ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

Notes

The vi editor has an insert mode and a command mode. You can call up insert mode with the [i] key. In this mode, the characters entered are immediately inserted into the text. To call up command mode, press [ESC]. If you use command mode, your keyboard input is interpreted as a command.

To exit vi and save the file, enter the command :wq and then press Enter.
Replace the existing entries with the following information:
NAME=Public_NAME_OF_NETWORK_INTERFACE
TYPE=Ethernet
DEVICE=NAME_OF_NETWORK_INTERFACE
ONBOOT=yes
BOOTPROTO=none
IPADDR=PRIMARY-IPV4-ADDRESS
PREFIX=32
GATEWAY=10.255.255.1
DNS1=DNS-SERVER 1
DNS2=DNS-SERVER 2
IPV6INIT=yes
IPV6_AUTOCONF=no
DHCPV6C=no
IPV6ADDR=PRIMARY-IPV6-ADDRESS/64
IPV6_DEFAULTGW=fe80::1%NAME_OF_NETWORK_INTERFACE
Replace the placeholder NAME_OF_NETWORK_INTERFACE in all places with the network interface you have determined.
Replace the placeholder in the IPADDR line with the main IPv4 address.
For DNS1 and DNS2, enter the DNS servers that you have noted.
Replace the placeholder in the IPV6ADDR line with the main IPv6 address.
Enter the IPv6 gateway in IPV6_DEFAULTGW and replace the placeholder NAME_OF_NETWORK_INTERFACE with the determined network interface.
To configure the additional IPv4 address(es), add the following entry(s):
IPADDR1=ADDITIONAL_IPV4-ADDRESS
PREFIX1=32
IPADDR2=ADDITIONAL_IPV4-ADDRESS
PREFIX2=32
IPADDRN=ADDITIONAL_IPV4-ADDRESS
PREFIXN=32
Replace the ADDITIONAL_IPV4_ADDRESS part with the desired additional IPv4 address.
To configure additional IPv6 addresses, add the following entry:
IPV6ADDR_SECONDARIES=ADDITIONAL_IPV6-ADDRESS/64
Replace the ADDITIONAL_IPV6_ADDRESS part with the desired additional IPv6 address. To configure several additional IPv6 addresses, enter them one after the other. Use a space to separate the IPv6 addresses.
The following example shows a complete entry that is used to configure the main IPv4 and the main IPv6 address as well as an additional IPv4 and an additional IPv6 address.
NAME=Public_eth0
TYPE=Ethernet
DEVICE=eth0
ONBOOT=yes
BOOTPROTO=none
IPADDR=217.160.44.181
PREFIX=32
IPADDR1=217.160.45.196
PREFIX1=32
GATEWAY=10.255.255.1
DNS1=212.227.123.16
DNS2=212.227.123.17
IPV6INIT=yes
IPV6_AUTOCONF=no
DHCPV6C=no
IPV6ADDR=2001:8d8:1800:832d::1/64
IPV6ADDR_SECONDARIES=2001:8d8:1800:832d::2/64
IPV6_DEFAULTGW=fe80::1%eth0
To exit vi and save the file, enter the following command and then press Enter:
:wq
To restart the server, enter the following command:
[root@localhost ~]# systemctl reboot
Log in to the server again.
To check whether the desired IPv4 and IPv6 addresses have been configured correctly, enter the command ip addr show:
[root@localhost ~]# ip addr show

Note

If the server is no longer accessible due to a configuration error, you can log in to the server using the Rescue System and correct the configuration.