IBM Support

Resetting Network in VIOS (Virtual I/O Server)

Troubleshooting


Problem

This document describes how to view the VIOS network configuration and reset the network, if needed.

Resolving The Problem

To view the current network configuration, issue the following commands:

lsdev | grep ^e
lsmap -all -net
lstcpip -num

Sample configuration (adapter number may change) follows:

o Virtual adapters are assigned to a virtual network: ent 2, 3, 4, 5....
o VIOS Bridges a vlan using Shared Ethernet adapter: ent6. This has the external VIOS IP address.
o LHEA (Logical Host Ethernet Adapter): Only the first LHEA is configurable. It is the backing device for the SEA (Shared Ethernet Adapter). ent0 physical HEA (Host Ethernet Adapter) port.

Problem

The VIOS interface is on the LHEA instead of the SEA. The LPARs can no longer be reached from the network. IVM (Integrated Virtualization Manager) no longer shows the SEA in View/Modify network settings. Instead, it shows the LHEA, and the IP is assigned to an interface on the LHEA. In addition, any attempt to remove or alter the virtual Ethernet seems to fail, complaining about the SEA(s) that is not configured: "you may not bridge one physical adapter (ent0) to multiple virtual Ethernets."

    • - Example of invalid configuration



      lstcpip -num
      Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Coll
      en0 1500 link#2 0.1a.64.44.1e.8 38991 0 1479 0 0
      en0 1500 9.5.30 9.5.30.82 38991 0 1479 0 0 <<<<<<<<<<<<Interface is on the LHEA

      lsmap -all -net:
      SVEA Physloc
      ------ --------------------------------------------
      ent4 U7998.61X.100113A-V1-C3-T1

      SEA ent8
      Backing device ent0
      Status Available <<<< Status will show available
      Physloc U78A5.001.WIH01E0-P1-T6

      SVEA Physloc
      ------ --------------------------------------------
      ent5 U7998.61X.100113A-V1-C4-T1

      SEA NO SHARED ETHERNET ADAPTER FOUND

      SVEA Physloc
      ------ --------------------------------------------
      ent6 U7998.61X.100113A-V1-C5-T1

      SEA NO SHARED ETHERNET ADAPTER FOUND

      SVEA Physloc
      ------ --------------------------------------------
      ent7 U7998.61X.100113A-V1-C6-T1

      SEA NO SHARED ETHERNET ADAPTER FOUND

      • - Example of a valid configuration



        $ lstcpip -num

        Name  Mtu   Network     Address           ZoneID    Ipkts Ierrs    Opkts Oerrs  Coll
        en8   1500  link#2      0.1a.64.44.1e.8          47829588     0   457285     0     0
        en8   1500  9.5.30      9.5.30.82                47829588     0   457285     0     0 <<<<<<<<<<<<Interface is on the SEA
        lo0   16896 link#1                                 327632     0   331070     0     0
        lo0   16896 127         127.0.0.1                  327632     0   331070     0     0
        lo0   16896 ::1                                0   327632     0   331070     0     0

        $ lsmap -all -net
        SVEA   Physloc
        ------ --------------------------------------------
        ent4   U7998.61X.100113A-V1-C3-T1

        SEA                   ent8
        Backing device        ent0
        Status                Available
        Physloc               U78A5.001.WIH01E0-P1-T6

        SVEA   Physloc
        ------ --------------------------------------------
        ent5   U7998.61X.100113A-V1-C4-T1

        SEA                   ent9
        Backing device        ent1
        Status                Available
        Physloc               U78A5.001.WIH01E0-P1-T7

        SVEA   Physloc
        ------ --------------------------------------------
        ent6   U7998.61X.100113A-V1-C5-T1

        SEA                 NO SHARED ETHERNET ADAPTER FOUND

        SVEA   Physloc
        ------ --------------------------------------------
        ent7   U7998.61X.100113A-V1-C6-T1

        SEA                 NO SHARED ETHERNET ADAPTER FOUND



      Resolution

      The IP should belong to the SEA. Once you create an SEA, you must put any TCP configuration on the SEA interface, not the physical interface. The following procedure can be used if the SEA adapter already exists:

      Where X is the physical Interface, and Y is the SEA interface:

      chdev -dev enX -attr state=detach
      rmdev -dev enY
      shutdown -restart (cfgdev might have re-created enY without a reboot)
      chdev -dev enY -attr state=up -restoreroute
      mktcpip -hostname intvios1 -inetaddr 9.5.30.50 -interface enY -gateway 9.5.30.1 -nsrvaddr 9.10.244.200 -nsrvdomain rchland.ibm.com -netmask 255.255.255.0 -start


      To completely reset the network configuration, do the following:
      1. Open VIOS command line interface:

      There are several ways to do this. You can either open a console session from HMC. Telnet to VIOS partition. Use PuTTY to connect to the VIOS partition. If you are using IVM to a blade, PuTTY or telnet to the blade center chassis and then open a console to the blade in question.

      Reason: You can remove all of your networking when performing the steps in this document. If you remove the interface you are using to access VIOS, your session will hang. If you PuTTY or telnet to the bladecenter, and then use `env -T blade[X], you are accessing the blade using Serial-Over-LAN, and deleting interfaces should not impact your session communication.
      2.Delete all existing network devices and from the VIOS command line interface:

      lsdev | grep -i "Shared Ethernet"
      rmtcpip -all
      rmdev -dev enX (where X is the number of the Shared Ethernet adapter(s)
      rmdev -dev etX
      rmdev -dev entX
      3.Re-create the LHEA and virtual adapters by either:

      cfgdev

      OR

      Reboot VIOS:

      shutdown -restart

      lsdev | grep ^e (View newly created LHEAs)
      4.Re-create your SEA:

      mkvdev -sea ent0 -vadapter ent2,ent3,ent4,ent5 -default ent2 -defaultid 1 (where ent0 is the Logical Host Ethernet Port and ent2 to ent5 are the Virtual I/O Ethernet Adapters)

      Note: For non-blade environment, we need to ensure the HEA is in promiscuous mode with the vios lpar being the promiscuous lpar. See Step 5 in Rochester Support Center knowledgebase document N1013928, Configuring the Host Ethernet Adapter for Use by the System i:
      5.Re-create your network interface with 'mktcpip' (or use configassist to get smitty screens):

      mktcpip -hostname intvios1 -inetaddr 9.5.30.50 -interface en6 -gateway 9.5.30.1 -nsrvaddr 9.10.244.200 -nsrvdomain rchland.ibm.com -netmask 255.255.255.0 -start

      where ent6 is the SEA, en6 is the corresponding device for ent6 which is the device description.

      [{"Product":{"code":"SSPHKW","label":"PowerVM Virtual I\/O Server"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Component":"--","Platform":[{"code":"PF012","label":"IBM i"}],"Version":"6.1;6.1.1;6.1.0;6.1.1","Edition":"","Line of Business":{"code":"LOB57","label":"Power"}}]

      Historical Number

      488684482

      Document Information

      Modified date:
      19 February 2022

      UID

      nas8N1018747