Resetting Network in VIOS (Virtual I/O Server)

Technote

 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:

1.       Virtual adapters are assigned to a virtual network: ent 2, 3, 4, 5....

2.       VIOS Bridges a vlan using Shared Ethernet adapter: ent6. This has the external VIOS IP address.

3.       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
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 <<<<<<<<<<<

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
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 <<< <<<<<<<<<
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 475229366, 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.