Today I tried to add a virtual Terminal Server within a XenServer to a NLB cluster. The current NLB cluster contained only physical servers. When adding the virtual server to the NLB cluster with the NLB manager, the server lost all IP communication. It isn’t possible to connect to or from the server. Together with the system administrator, we searched multiple forums and we found the solution to the problem.
It looks like XenServer doesn’t support multicast by default, because of the bridge design of the network interfaces. We found an interesting article on the internet to enable multicast on the virtual interface.
In the end we took the following steps to enable multicast support on the virtual interface of the XenServer.
# Retrieve the DOMID of the virtual server
xe vm-list name-label=<VMNAME> params=dom-id
# Enable multicast on the virtual interface of the virtual server
ifconfig vif<DOMID>.0 multicast
We restarted the virtual server and the DOMID changed, but multicast with IGMP support was still working and the server was still part of the NLB cluster. The system administrator will do some more testing and he will try to add another virtual server to the NLB cluster.
More and more people would like to implement OTP (One Time Password) solutions. RSA is one of multiple vendors for OTP solutions. I also notice the wish to implement and support OTP with on-demand tokens, like SMS and e-mail.
RSA supports on-demand tokens, but the minimum RSA Authentication Manager version required is 7.1. Not only on-demand tokens, but also virtualization (like VMware) is very hot. For a long time, RSA 7.1 was only supported on physical servers. Running RSA 7.1 on a physical server doesn’t always perform very well, especially compared to RSA 6.1. This version performs well on a physical server as well on a virtual server.
I guess I have to install this version under ESX to see how it performs, but maybe someone can tell me their own experience….