Add secondary IP to Network Adapter Windows

A web developer was adding IP’s to some existing web server and once these were added we started having routing issue on the servers where the sites would not respond and the server could not talk back to the production network from the DMZ.

I checked the server and I was getting inconsistent results as I could ping a device sometimes but not others so it looked like a network issue.

I ran the below command to check what traffic was being sent and I saw that there where multiple IP’s being used as local address for traffic.

Get-NetTCPConnection -LocalAddress 192.168.0.*

I decided to check the skipasSource on the interface as this was the cause of a similar issue that happened before.

This command’s will return all IP’s the interface name and whether the IP is set to skipassource the new IP should have this set to true.

CMD:                                                                                                                                               

Netsh int ipv4 show ipaddresses level=verbose

PowerShell:                                                                                                                                       

Get-NetIPAddress | Select-Object IPAddress, InterfaceAlias, SkipAsSource

When I checked the new IP was set to false which meant both the orignal and new IP where being used. To set the IP to false I either need to remove the IP and set it using cmd or PowerShell  to set skip as source to true or Set to true using PowerShell.

If you don’t want to remove and re-add the address use the below command

Set-NetIPAddress -IPAddress "192.168.0.200" -InterfaceAlias "LAN" -SkipAsSource $false

second option is to remove the IP from the network settings and  re-add the IP using command line below is using CMD and PowerShell.

CMD:           

Netsh int ipv4 add address “Interface Name” “IP Address” “Netmask” skipassource=True                                                                                                                                 

Below is a full example:

Netsh int ipv4 add address "LAN" 192.168.0.200 255.255.255.0 skipassource=true

PowerShell:                                                                                                                                     New-NetIPAddress –IPAddress “IPAddress”  –InterfaceAlias “Interface Name” –SkipAsSource $True

Below is a full example:

New-NetIPAddress –IPAddress 192.168.0.200 -PrefixLength 24 -InterfaceAlias "LAN" –SkipAsSource $True

Once skip as source was set to true there was no connection issues.