AIX

Note: Newbie to IBM virtualization :-)
Query: Created a new AIX7.1 lpar on a system with same config as one before however the new one is having issues going out to physical network.
Now on comparison the only thing which differs between these two machines is an additional en1 and ent1 shown below in table. I'm not sure if they were added manually by executing some command or something so any help in how should I debug this will help.

Please note that both LPARs have same virtual adapter configurations including same VLAN ID and same additional VLAN added with 802.1q enabled.

Please post the output of ifconfig or a similar command on your machines which shows the network hardware interface details for both machines.

Hello Neo
Thanks for the quick response.


ifconfig for both machines is exactly the same other than of course the ip change. Here is one of the two

Code:

working::/ # ifconfig -a
en1: flags=1e084863,480<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,CHECKSUM_OFFLOAD(ACTIVE),CHAIN>
        inet xx.xx.xx.xx netmask 0xfffffc00 broadcast 10.0.227.255
         tcp_sendspace 262144 tcp_recvspace 262144 rfc1323 1
lo0: flags=e08084b,c0<UP,BROADCAST,LOOPBACK,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,LARGESEND,CHAIN>
        inet 127.0.0.1 netmask 0xff000000 broadcast xx.xx.xx.xx
        inet6 ::1%1/0
          tcp_sendspace 131072 tcp_recvspace 131072 rfc1323 1

I guess my first question is when is an interface of type VLAN created for a LPAR; 'ent1' in my case? Since en1 and ent1 is missing on the new lpar I'm just trying to figure out what it means and when it gets created.

Just to be clear both LPARs have same virtual adapter configurations and hence I was expecting the same number of interfaces being visible in lsdev output.

Code:

bash-4.4# lsdev | grep ^en
en0        Defined         Standard Ethernet Network Interface
 en1        Available       Standard Ethernet Network Interface
ent0       Available       Virtual I/O Ethernet Adapter (l-lan)
ent1       Available       VLAN

Code:

bash-4.4# lsdev -C -H -S a -F 'name class subclass type'
name       class     subclass  type
en1        if        EN        en
ent1       adapter   vlan      eth
<--more rows truncated -->

It's hard for me to comment, since you are only posting the configuration information for one machine and not both, side-by-side, so we can carefully compare the two together to insure they are the same; or identify any differences.

There are such a number of possible causes to this that we will need to narrow it down a bit first. Here is how (in general) AIX virtualisation in respect to networks work:

You have one (if you have IVM, two if you have a HMC) VIOS servers in each hardware box. "VIOS" means "virtual I/O server") and these are LPARs running a special version of AIX (called "IOS") used to virtualise hardware which can't easily be virtualised otherwise, i.e. network cards. That means: you have VIOS servers which have the physical network card(s) assigned as ressources. In the VIOS you create a virtual network card which is based on some physical connection (a quite common setup is to have Etherchannels consisting of several physical network cards bonded and base the virtual adapter on that) and this virtrual card is given to the LPAR as a resource. The VIOS acts as a bridge with an internal VLAN system so that it can redirect cleanly the traffic to/from the various LPARs it serves.

So, first question: did you create a new virtual adapter in the VIOS when you created the new LPAR?

Second: you need to configure the VLANs for inside and outside the phyiscal system where the LPAR is based on correctly for the network connection to work. If you need help with this you will need to tell us a bit more about your network, its VLANs and the configuration of the NIC in the VIOS as shown in the HMC/IVM.

I hope this helps.

bakunin

Thanks for the info Bakunin.



I created virtual adapters in both VIOSs however they were for ISCSI disk interfaces. The virtual adapter for network was created in LPAR and not VIOS. While creating this virtual adapter the PVID was kept same as that of the PVID of existing adapter in VIOS. This is something which is getting followed from past and I don't have enough documentation to know why. The overall setup looks like this:



Env is HMC based
Two VIOS partitions
One NIM partiion


Virutal Ethernet adapter in VIOS looks like this

Code:

Adapter ID:2Virtual switch:ETHERNET0Port Virtual Ethernet (VLAN ID):xx:FalseIEEE 802.1q compatible:TrueAdditional VLAN IDs:xxxx  xxxx  Access external network:TrueTrunk priority:1

Virtual ethernet adapter in new LPAR looks like this

Code:

Adapter ID:2Virtual switch:ETHERNET0Port Virtual Ethernet (VLAN ID):xxRequired:FalseIEEE 802.1q compatible:TrueAdditional VLAN IDs:xxxx  Access external network:False

Now my understanding was LPAR adapter will get mapped to VIOS adapter via the PVID which is same for both. And additional VLAN IDs added here are for external network.
The problem I'm seeing is that external network is not reachable from the new LPAR and the only difference between new and old lpar(which is working fine) is an additional interface in old LPAR of type VLAN.
en1 and ent1 below are missing in new LPAR.

Code:

old-lpar# lsdev | grep ^en
en0        Defined         Standard Ethernet Network Interface
 en1        Available       Standard Ethernet Network Interface
ent0       Available       Virtual I/O Ethernet Adapter (l-lan)
ent1       Available       VLAN

Now I'm wondering if this VLAN type interface was somehow manually created earlier for some specific config handling or if it's something which was getting created automatically when the LPAR virtual ethernet adapter was created earlier but now is not happening because of some bug or something which is broken in the HMC environment. I'm not sure if this is the root cause though unless I've it in new LPAR as well.

Few questions for my clarity:
Q1> What is this interface of type VLAN stand for and when does it get created.
Q2> If LPARs(multiple) and VIOS all have same PVID then all LPARs should be able to communicate directly without involving VIOS. And then the additional VLAN ids added to LPAR adapter and VIOS adapter are to take care of external network communication. Is this understanding correct?

Hmmmm,
the "PVID" is the "physical volume ID" and is the property of a (physical or virtual) disk - it has absolutely nothing to do with networks at all. It is an identifier of the disk, quite like the UUID in Linux, by which the device is identified in the volume group.

Show the profile (from the HMC) of the new lpar. I suppose it doesn't have a virtual network adapter as resource. You need to create this on the VIOS first, then add it to the LPAR profile. only then you can start and install the system successfully. I suggest you read the IBM documentation, i.e. these articles:

Configuring a virtual Ethernet adapter
Configuring virtual Ethernet on the Virtual I/O Server
Virtual adapters

It is simply to complex to walk you through the whole process via a forum without knowing all the details of your environment because there are so many ifs and buts and althoughs involved. So, if you have some specific questions after reading up about the IBM virtualisation or if you need some general principles explained i'd be glad to help but what i think your problem is would be best solved by hiring a knowledgeable person and let this person do it for you, eventually teaching you about how it is done in the process.

To get you some further pointers on where you (presumably) stand: You have probably a SEA (shared ethernet adapter) configured on the VIOS (this is the common setup i talked of before). You need to base the virtual adapter on this. There is a HMC screen where you can do that - depending on which HMC version you use because the menus changed between the "classic" and the "enhanced" version ("enhanced" being an euphemism for "nearly unusable", but that is another story) you will find it in different panels. Honestly, i have no HMC at hand and can't you talk you through the menus off the top of my head.

Once you have this adapter defined (you need to do it for both VIOS) you need to add it to the profile of the LPAR, then start the LPAR anew. Notice that rebooting is NOT sufficient. You need to shutdown -h, then start it again.

I hope this helps.

bakunin