Latest download of Zookeeper binaries

Hi Where can I find the latest binaries of Zookeeper? None of the download links off the Apache site seem to work. Avinash

Watches - is delivery guaranteed?

Hi All Suppose I have a znode, say /Me, and have three nodes A, B and C who have set watches on this znode. Now suppose some process changes some value on /Me then watches get delivered to A, B and C. Now if at that instant of time C were down I could always read the znode on coming back up.

Watches

Hi All Is it possible to have 100K machines register for a watch on a znode? I mean theoritically yes it should work but ZK scale to these many instances when it comes to delivering watch notifications? Perhaps no one has practical experience in dealing with this but is there any fundamental

Re: API for node entry to the cluster.

, a) reconfigure and restart each surviving node b) kill the node(s) that is(are) leaving you now have a smaller cluster. On Thu, Nov 5, 2009 at 11:02 AM, Avinash Lakshman avinash.laksh...@gmail.com wrote: Hi All Is it possible to remove nodes and add nodes dynamically to the ZK cluster

Re: API for node entry to the cluster.

you clarify what you mean? I halfway suspect you dropped a word somewhere. On Thu, Nov 5, 2009 at 11:24 AM, Avinash Lakshman avinash.laksh...@gmail.com wrote: I would prefer not restarting. Start/Stop the new/old process and then start a round of consensus for adding/removing a machine

API for node entry to the cluster.

Hi All Is it possible to remove nodes and add nodes dynamically to the ZK cluster via API? Any plans in the future to do this? TIA A

Usage of myId

Why is this important? What breaks down if I have 2 servers with the same myId? Cheers A

Recovery protocol

Hi All Let's say I have a Zookeeper cluster with nodes A, B, C, D and E. Let's assume A is the leader. Now let us assume after a few writes have taken place the node B crashes. When it comes back up what is the recovery protocol? Does it join the cluster immediately and start taking writes and

What does this exception mean?

Hi All I run into this periodically. I am curious to know what this means, why would this happen and how am I to react to it programmatically. org.apache.thrift.TException: org.apache.zookeeper.KeeperException$ConnectionLossException: KeeperErrorCode = ConnectionLoss for /Config/Stats/count

Adding observers

Hi All I have two questions regarding Observers in ZK. (1) Is it possible to increase the number of observers in the cluster dynamically? (2) How many observers can I add given that I will seldom write into the cluster but will have a lot of reads coming into the system? Can I run a cluster with

Re: Adding observers

Sorry as an addendum I had one more question. (1) If I snapshot the data on other observer machines will I be able to bootstrap new observers with it? Given that writes are like a one time thing. Cheers A On Wed, Jul 21, 2010 at 10:30 AM, Avinash Lakshman avinash.laksh...@gmail.com wrote

Re: Adding observers

Any example scripts for the rolling restart technique that anyone would be kind enough to share? Thanks Avinash On Wed, Jul 21, 2010 at 10:44 AM, Henry Robinson he...@cloudera.com wrote: Hi Avinash - (1) Is it possible to increase the number of observers in the cluster dynamically? Not

Logs and in memory operations

Hi All From my understanding when a znode is updated/created a write happens into the local transaction logs and then some in-memory data structure is updated to serve the future reads. Where in the source code can I find this? Also how can I decide when it is ok for me to delete the logs off

Zookeeper CLI

I have a 5 server ZK cluster. I want to connect to it using the CLI from some remote machine. Is there any particular set up that I need to connect? I am running it as zkCli.sh -server server name where the server name is one of the servers in the ZK cluster. Is this correct? I can get a string of

Re: Zookeeper CLI

On 7 September 2010 16:48, Avinash Lakshman avinash.laksh...@gmail.com wrote: I have a 5 server ZK cluster. I want to connect to it using the CLI from some remote machine. Is there any particular set up that I need to connect? I am running it as zkCli.sh -server server name where the server

ZooDefs.Sync

What is a Sync OpCode stand for? In particular what does a LearnerSyncRequest represent? Thanks Avinash

Too many connections

I find this happening in my observers node in the logs. The observers are running in a different data center from where the ZK non-observers are running. The only way to fix this seems to be restarting. How can I start addressing this? Here is the stack trace. Too many connections from

Re: Too many connections

, Avinash Lakshman avinash.laksh...@gmail.com wrote: I find this happening in my observers node in the logs. The observers are running in a different data center from where the ZK non-observers are running. The only way to fix this seems to be restarting. How can I start addressing this? Here

Re: Too many connections

are running in a different data center from where the ZK non-observers are running. Could you have a NAT or some other networking configuration that makes all the observers seem to be coming from the same IP address? Patrick On Tue, Oct 5, 2010 at 9:33 AM, Avinash Lakshman avinash.laksh

Re: Zookeeper on 60+Gb mem

I have run it over 5 GB of heap with over 10M znodes. We will definitely run it with over 64 GB of heap. Technically I do not see any limitiation. However I will the experts chime in. Avinash On Tue, Oct 5, 2010 at 11:14 AM, Mahadev Konar maha...@yahoo-inc.comwrote: Hi Maarteen, I definitely

snapshots

Hi All Are snapshots serialized dumps of the DataTree taken whenever a log rolls over? So when a server goes down and comes back up does it construct the data tree from the snapshots? What if I am running this on a machine with SSD as extended RAM how does it affect anything? Cheers A

Changing configuration

Suppose I have a 3 node ZK cluster composed of machines A, B and C. Now for whatever reason I lose C forever and the machine needs to be replaced. How do I handle this situation? Update the config with D in place of C and restart the cluster? Also if I am interested in read just the ZAB portions

Re: What does this mean?

processes of different clusters? ben From: Avinash Lakshman [avinash.laksh...@gmail.com] Sent: Sunday, October 10, 2010 8:18 AM To: zookeeper-user Subject: What does this mean? I see this exception and the servers not doing anything

Membership using ZK

This is what I have going: I have a bunch of 200 nodes come up and create an ephemeral entry under a znode names /Membership. When nodes are detected dead the node associated with the dead node under /Membership is deleted and watch delivered to the rest of the members. Now there are

Re: Membership using ZK

AM, Avinash Lakshman wrote: This is what I have going: I have a bunch of 200 nodes come up and create an ephemeral entry under a znode names /Membership. When nodes are detected dead the node associated with the dead node under /Membership is deleted and watch delivered to the rest

Unusual exception

I started seeing a bunch of these exceptions. What do these mean? 2010-10-13 14:01:33,426 - WARN [NIOServerCxn.Factory: 0.0.0.0/0.0.0.0:5001:nioserverc...@606] - EndOfStreamException: Unable to read additional data from client sessionid 0x0, likely client has closed socket 2010-10-13 14:01:33,426