Logical Network RHEV-M 3.2

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Hello

I have the following enviroment

- 4 physical host with RHEV 6.4

- 1 physical host with RHEV-M 3.2

- 1 Storage Equallogic 

We have 2 Logical Network

- Storage (Connection Subnet Storage 10.10.10.xxx)

- rhevm (Management 192.168.10.xxx)

We need to create a network logical that a member of the network logical rhevm as VMWare vswitch settings, where you have network management and assigns a vswitch to create virtual machines (VMKernel)

Need to know if it is possible to perform the above settings, then create a new logical network and assign virtual machines but not accessible from the network if the logical network has no  IP.

 

Thanks for your help.

Responses

Hi Sebastian. If the community can't help out with an answer for this one, you may need to open a Red Hat support case.

I don't know how VMware works in this case to give you a reply on how this can be achieved in RHEV. Is it possible to draw a network diagram of what you are looking for so that I can easily understand and help you on this?

Hi Sebastian -

I remember reading this last week and thinking I could maybe help, but I'm not quite sure what you're looking for.  

> Need to know if it is possible to perform the above settings, then create a new logical
> network and assign virtual machines but not accessible from the network if the logical
> network has no  IP.

I think what you want to do is set up another logical network in addition to your rhevm and storage networks, correct?  And then you want to connect some of your VMs to this logical network such that they isolated and can only see each other.  Still correct?

In VMware, you can use the GUI to set up a vSwitch with no logical connection to a physical NIC, and then connect VMs to that vSwitch. You end up with a virtual network for those VMs with no path to the outside.  I think you want to set up something similar with RHEV.  

I just tinkered with this in my own RHEV 3.2 setup.  Create a logical network named, say, GregTest, attach it to a data center and cluster, then connect some VMs to it.  But my RHEV-M GUI did not give me any choice to do that.  Looks like network GregTest needs to be associated with a physical NIC on each host in order for anything to use it.   I have an unused NIC on my hosts, so I associated logical network GregTest with my unused NIC, eth1, on each host.  Now I can connect my test VM to logical network GregTest. Physical NIC eth1 is not connected to anything, so that made a mess of my hosts, data center, and cluster as everything went non-operational.  RHEV is picky this way - the hosts have to see each other on every path.   Do not try this at home.  Well - maybe only try this at home I guess.  

Plan B -  how about setting up a logical network with a VLAN tag not used anywhere else?  Associate this logical netowrk with the same physical NIC as either your rhevm or storage networks.  Now you can connect VMs to this logical network and they should be isolated.   Unless you make a virtual router with 2 NICs, one in the rhevm network, the other in your VLAN tagged network.  

I just tried plan B in my own setup and it seems to work without making a mess of my hosts.  I can only move powered off VMs from one logical network to another.  But my hosts, cluster, and data center are still at RHEV 3.1 compatability, so this restriction **may** be lifted when all the objects are at 3.2.  Maybe.  

- Greg Scott

Hey Greg,

You can assign a NIC that is not in use, but you have to make sure that the checkbox for Required is not selected.  Or, as you found, it will put the node in a non-operational state and things get messy.  You can view all the networks by selecting your Cluster and then Logical Networks.

This is actually a very important thing to know as I feel that they don't emphasize this point enough.  I would NEVER make any Logical Network a required resource for a cluster unless there were more than one NIC and on separate physical switches.