Configuring the Instance OS for a Secondary IP Address

Linux Instance OS Configuration 🔗

This configuration permits use of an IP address subnet, netmask, gateway, and DNS service that are entirely independent from the existing NIC. This configuration is persistent across reboots.

Create a new network interface configuration file to create a subinterface on the existing NIC. In this example, ens03 is the name of the existing NIC and ifcfg-ens3:0 is the name of the new configuration file.

1. Create the network configuration file ifcfg-ens3:0 in the /etc/sysconfig/network-scripts/ directory to create the first sub-interface (:0) on the existing ens3 NIC.

   Include the following entries in ifcfg-ens3:0:

   TYPE=Ethernet
   BOOTPROTO=none
   IPADDR=a.b.c.d
   PREFIX=24
   GATEWAY=
   DNS=
   NAME=ens3:0
   DEVICE=ens3:0

2. Include the appropriate IPADDR, PREFIX, GATEWAY, and DNS entries for this new sub-interface.

3. Run the following command to start the new interface:

   # ifup ens3:0

4. Run the following command to confirm that the new interface is operational:

   # ifconfig -a

See also Linux: Details about Secondary IP Addresses.

Oracle Solaris Instance OS Configuration 🔗

Use the ipadm command to configure network interfaces persistently.

Microsoft Windows Instance OS Configuration 🔗

See Windows: Details about Secondary IP Addresses for information about how to either:

• Create a PowerShell script.

• Use the Network and Sharing Center user interface.