Hi Dojo,
We have a 1+1 Failover configuration on our DMAs. And have the following hostnames:
- DMAa: Physical IP DMA A
- DMAb: Physical IP DMA B
- DMAv: virtual IP
When we currently do an “nslookup DMAv” we get the Virtual IP returned. And we would like to see the Physical IP of either DMA A or DMA B, dependent on which one is currently active.
When we look at the configuration on the Active DMA, we see that the virtual IP is set as primary. The Physical IP is set as secondary and with the “skip as source” = true setting. This means it will NOT be registered in the DNS.
Is there any way we could get the “nslookup DMAv” to show the Physical IP of the agent which is currently active?
Would the following be a viable possible solution?:
- the virtual IP to be shared and managed by a Windows Server Cluster which would allow both to be registered as source, but the virtual ip be used only for the services registered in the windows cluster
Hi Stacey,
What is the exact use case here? Why is there a need to get the physical IP address?
The entire concept of Failover (with VIP) is that two machines are transparently presented to the outside world as one single machine, hosted on the virtual IP address. In this setup, physical IP addresses are considered private to the failover pair. DataMiner applying the SkipAsSource flags on all but the virtual IP address is part of this.
In recent DataMiner versions, Failover can also be configured without the use of a virtual IP address. In that case, a shared hostname will resolve to the IP addresses of both machines. Either the client then makes sure to connect to the correct one, or the DataMiner agents forward requests to each other.
For your use case, you might also be able to use the PowerShell script hooks which are available when assigning/removing a virtual IP (in versions 10.1.3+/10.2+/RN28236). These might allow you to execute custom code that registers a custom DNS name with the physical IP address when the VIP gets assigned.
An extra alternative idea: put a file called agentname.txt on both agents in the Web folder with the name of the agent inside. You could then request http://dmav/agentname.txt to get the name of the currently active agent.
Or use “arp -a 1.2.3.4” (where 1.2.3.4 is the virtual IP) to get the MAC address of the machine which is online (and map that one to a name)
To avoid confusion:
The nslookup should result in correct IP adresses per DMA:
nslookup DMAa -> IP of DMAa
nslookup DMAb -> IP of DMAb
nslookup DMAv -> virtual IP
When we do a nslookup on DMAb and b is ucrrently active the virtual IP is resolved and not the physical IP of DMAb as expected.
Hi Wouter,
The use-case of the customer is that they would be able to easily determine with this nslookup which agent is currently the Active one in the system.
I will bring forth your suggestion to use a powershell script hook.