Additional IP addresses (Host)
Setting up additional single IPv4 addresses
It is currently possible to obtain up to 3 additional single IPv4 addresses. Should further addresses be required, you may apply for a subnet.
The IP addresses can be temporarily used in two different ways:
- ifconfig eth0:1 10.4.2.1 netmask 255.255.255.255
- or
- ip addr add 10.4.2.1/32 dev eth0
CentOS
A permanent configuration is only possible by default via alias interfaces (eth0:1, eth0:2 etc.). A file needs to be created for each IP address:
/etc/sysconfig/network-scripts/ifcfg-eth0:1 /etc/sysconfig/network-scripts/ifcfg-eth0:2
These files must include the following information:
DEVICE=eth0:1 BOOTPROTO=none ONBOOT=yes IPADDR=<IP Address> NETMASK=255.255.255.255
Finally, a “service network restart” needs to be initiated or the server needs to be restarted (“reboot”).
Please note: A different configuration is needed for the use of IP addresses in virtual machines!
Fedora
For a permanent configuration the IP addresses can be added to the configuration file:
# cat /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE="eth0" ... IPADDR=192.0.2.1 NETMASK=255.255.255.240 IPADDR0=192.0.2.10 # Additional IP PREFIX0=28 IPADDR1=192.0.2.11 PREFIX1=28 IPADDR2=...