Problems with TCP/IP over virtual Ethernet

Verify that the TCP/IP configuration for the point to point virtual Ethernet is correct. If the i5/OS TCP/IP configuration is new or has changed, perform the following procedure to verify that the TCP/IP configuration in Windows is correct.

1. Click Start —> Control Panel —> Network Connections or Start —> Settings —> Network and Dial up Connections.
2. Right click Network Connections or Network and Dial-up Connections to show a popup menu and select Open.
3. Double-click IBM iSeries Virtual Ethernet point to point Connection.
4. Click on the Properties button.
5. Select the Internet Protocol (TCP/IP)
6. Click on the Properties button. If the Use the Following IP Address is selected and the IP address from the i5/OS console is displayed, you do not need to proceed any further. If the Obtain an IP address automatically is selected, continue with the next step.
7. Select the radio button: Use the Following IP Address.
8. On an i5/OS command line, type the following command, where 'nwsd' is the name of the NWSD for your server, then press Enter; DSPNWSD NWSD(nwsd) OPTION(*TCPIP)
   • On the DSPNWSD dialog box, find the port named *VRTETHPTP. This shows the IP address and subnet mask values for the point to point virtual Ethernet.
   • On the integrated server console, type the point to point virtual Ethernet IP address and subnet mask values that were shown by the DSPNWSD command.
9. Click OK.
10. Click OK.
11. Click Close.

For information about verifying the TCP/IP configuration in i5/OS and Windows, see Explore point to point virtual Ethernet networks.

The point to point virtual Ethernet used by each active server must use a distinct IP subnet. To learn more about subnet requirements or to change the TCP/IP configuration, see Point to point virtual Ethernet IP address conflicts.

Verify that the iSeries Virtual Ethernet adapters are configured correctly and that they are working.

To troubleshoot a virtual Ethernet adapter, see one of the following topics.

• Virtual Ethernet problems with iSCSI attached servers.
• Virtual Ethernet problems with IXS and IXA attached servers

To verify that a line description is configured correctly for a virtual Ethernet adapter, see Manage virtual Ethernet and external networks.

Ensure that a firewall is not interfering.

If a firewall is involved, such as a software firewall running in Windows, it must be configured to allow required traffic.

• For the IP address of the IBM iSeries Virtual Ethernet point to point connection, allow TCP dynamic ports to prevent failure of integrated server administrative applications. Do not use Network Address Translation (NAT).
• For the IP address of an IBM iSeries Virtual Ethernet connection, allow protocols and ports required by your applications.
• For the IP address of an iSCSI HBA connection, see Configure a firewall.