dev@shoal.java.net

Re: [Shoal-Dev] Issues with cross subnet functionality

From: Mohamed Abdelaziz <Mohamed.Abdelaziz_at_Sun.COM>
Date: Mon, 08 Feb 2010 11:35:50 -0800

On 2/5/10 11:49 AM, Chandra Mulpuri wrote:
> Hi Shoal Developers,
>
> I have been evaluating Shoal for our highly scalable multi-node
> project here. Shoal seems pretty powerful and has all the
> functionality that we need. I see some issue in 1.1 though.
>
> 1) Exception in NetworkManager.java when VIRTUAL_MULTICAST_URI_LIST
> has just one IP Address.
> This is because of the following trace line in NetworkManager.java
> LOG.config("VIRTUAL_MULTICAST_URI_LIST=" + virtualMulticastURIList + "
> rendezvousSeedURIs.get(0)=" + rendezvousSeedURIs.get(1));
> If I pass only one tcp://<IP-address>:port to
> VIRTUAL_MULTICAST_URI_LIST, rendezvousSeedURIs.get(1) would be null.
>
> 2) If the Boot Strapping node is down, new member nodes joining and
> leaving the group are out of communication. To prevent this single
> point of failure, can all the nodes be Boot Strapping nodes ? Will
> there be any performance impact with this configuration ?

Essentially all nodes would multicast to one another, verses limiting it
to boot strapping nodes. For fail purposes, it is recommended that a
percentage proportional to the cluster size, take on that role.

Mohamed

>
> Thanks for your time,
> Chandra