Virtualized Oracle RAC and more…

Followers of my blog know I like doing virtual RAC installations.When I do these I’m focusing very much on the Oracle side of things, leaving the virtualization tool to handle the hardware virtualization, like networking and shared disk.

A few weeks ago Gilbert Standen contacted me to say he had done a virtual RAC installation using OpenvSwitch to virtualize the network components. He posted some basic tips. When I mentioned it on G+ and twitter, it generated some interest, so I suggested he write it up with a little more detail. That process has started now on his blog. You can see the first couple of articles here:

He tells me he’ll be adding more details to the posts when time permits.

If you are more focused on the network side of the infrastructure stack I think this is a really interesting proposition and well worth a read.

Cheers

Tim…

Author: Tim...

DBA, Developer, Author, Trainer.

6 thoughts on “Virtualized Oracle RAC and more…”

  1. Wanted to quickly post a note on an interesting application of openvswitch. Recently we had to move a production 11gR2 2-node RAC to a new network. This meant the public IPs, VIPs, and SCAN IPs had to all be moved to the new IP range. I tested it out on my 2-node virtualized RAC which uses openvswitch for the networking (instead of virtualbox “vboxnets”). The beauty of openvswitch was that there was no need to change anything at the switching or networking layer. The bridged adapters are attached to the linux “taps” which are assigned to the VLANs. Since all the switching is handled by the openvswitch layer 2 switching device using VLANs on the ports (the “taps”) there was no need to change anything whatsoever on openvswitch. Like a rose, is a rose, is a rose, so a VLAN, is a VLAN, is a VLAN and you can push whatever IP you want over it. So re-IP of the RAC involved simply following the instructions in Oracle Support Docs 276434.1 and 952903.1 all done on the linux server. If I had been using the vboxnets I would have had to re-IP my vboxnets. I will try to find time to add new posts at WordPress about this.

  2. Another quick post on the usefulness of openvswitch. Again, since I am using the openvswitch as a layer 2 switch, I can put different RAC deployments ontop of the same switch. The switch that I built for the 11gR2 virtual RAC is exactly the same switch I use for a 10gR2 legacy RAC which we are currently prototyping for some upgrade migration work. This means that once I have an openvswitch built which has in my case 4 dedicated VLANs (interconnect, public, DNS, and storage) I can use the taps for each of those VLANs without any reconfiguration needed. I like to build my prototypes of our production systems as close to actual, so I always use the actual IPs and actual static routes, etc. If I were using vboxnets, I’d have to have an ever-increasing number of vboxnets to accomodate all my RACs with different IP ranges. But with openvswitch used as layer 2 switch, just these 4 VLANs can support any RAC virtualized prototype no matter what the IP ranges are. Very useful.

  3. Recently I found out how to establish host-guest networking when you are using openvswitch as your complete VM switching solution for example for VirtualBox VMs. It is based on this page here: https://www.virtualbox.org/wiki/Advanced_Networking_Linux
    So, for example, I have an openvswitch “sw1” and a tap “s1”. I want to be able to connect to all my VirtualBox VMs which have a bridged adapter assigned to “s1” with “allow all” enabled as the promiscuity setting. Here’s how you do it:

    tunctl -t s1
    ip link set s1 up
    ovs-vsctl add-br sw1
    ovs-vsctl add-port sw1 s1
    ip link set up dev sw1
    ip addr add 10.207.39.1/24 dev sw1

    That’s it, now you have 2-way ssh between host and guest. You can look at your sw1 settings by command “ifconfig sw1”. Now you can ssh to any guest VM which has an IP in that subnet which is on a bridged adapter assigned to any other non-vlan’d tap on the switch. Note: don’t put a “tag=###’ where ### is a VLAN on the ports used for host-guest comm because so far, I haven’t found the way to get it to work when a VLAN is assigned.

    HTH,
    Gil Standen

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