Hi leehui.
leehui wrote:
>One of my question is what sorting algorithm is used?
Maybe the first member which is based on JXTA's net.jxta.id.ID in cluster view will become to be new master when a master is failed.
But net.jxta.id.ID doesn't means Shoal's server token(member's name). It is dependent on JXTA. So I think you can't guess what is new master in advance without logs.
If a master comes into collision with another master, only one master is selected with collision algorithm which is based on JXTA's ID.
And sorting algorithm is maybe java.lang.String's matching because of net.jxta.id.ID doesn't implement java.lang.Comparable.
leehui wrote:
>Another question, let's see a case. If node A, B, C jion the same group. Because of some network problems, A, B can communicate with each other, while >C can' t communicate with A and B. So, A, B will select a maste node. Let me assume it is A. And C will select itself as a master node. Is that right?
Right.
leehui wrote:
>After some time later, if A,B,C can communicate with each other, what is master node? A or C? Can B become a master node?
I think that this is very complex issue.
When one more masters exist in the group because of network problems and members join the group each other again after some time later,
I think that maybe two masters can exist in the same group.
If the group doesn't have a master, it is no problems because master collision algorithm works well in order to appoint the master as I said.
But if one more masters already exist, I think that current Shoal can't be aware of master's collision(this is my guess).
I don't know whether my knowledges about the master selection are correct or not.
But I hope this information helps you and I also would like to confirm this case. :-)
Thanks.
--
Bongjae Chang
----- Original Message -----
From: leehui
To: users
Sent: Friday, March 27, 2009 11:33 AM
Subject: [Shoal-Users] master node election question
Hi,
I have serveral questions about master node election.
From the doc on the shoal web site, I know that the group sorts all the members' token, and select the first node as master node. If the master node fails, then select the second node in the sorted list as the master node. Is that right?
One of my question is what sorting algorithm is used?
When a new member jion the group, how to assure it is not at the front of the sorted list?
Another question, let's see a case. If node A, B, C jion the same group. Because of some network problems, A, B can communicate with each other, while C can' t communicate with A and B. So, A, B will select a maste node. Let me assume it is A. And C will select itself as a master node. Is that right?
After some time later, if A,B,C can communicate with each other, what is master node? A or C? Can B become a master node?
Best Regard!
2009-03-27
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leehui