Changing data path deletes all buckets

Perry Krug added a comment - 04/Dec/12 8:32 AM As a note, changing the data path of 1 node in a cluster removes the buckets across the ENTIRE cluster. This command should only affect the node it is being run against...

Perry Krug added a comment - 04/Dec/12 11:40 AM Adding to documentation since there should be an extremely large warning about doing this on a live cluster until this bug is fixed. Note this is a regression from 1.x

Farshid Ghods added a comment - 04/Dec/12 11:44 AM similar bug here : http://www.couchbase.com/issues/browse/MB-7257 given that this is a regression and it actually impacts the entire cluster i recommend fixing this in 2.0

Aleksey Kondratenko added a comment - 04/Dec/12 11:52 AM Not similar but exactly same

Steve Yen added a comment - 04/Dec/12 2:25 PM per bug scrub, this doesn't look like dupe ... 7257 - 1.8: changes path without deleting data - 2.0: change deletes data, but can have documentation 7344 - 1.8: reconfigures node - 2.0: wipes entire cluster, not just node

Aleksey Kondratenko added a comment - 05/Dec/12 7:49 PM Decision was made to disallow procedure described in docs. As soon as cluster is provisioned, there's no way to change data path.

Perry Krug added a comment - 06/Dec/12 4:34 AM So we need a doc update on how to change the data path. It makes enough sense that you need to remove the node. Has the code been changed to prevent this from happening?

Aleksey Kondratenko added a comment - 06/Dec/12 12:36 PM Commit to prevent change of data path of provisioned cluster nodes is merged: http://review.couchbase.org/#/c/23113/

Farshid Ghods added a comment - 08/Dec/12 9:34 PM Hi Aliaksey, as part this change( http://review.membase.org/#/c/23113/ ) we made sure that if the node is provisioned the user will not be able to change the data path settings even though there are no buckets on the node. my question is what is the procedure now for a user who would like to change the data path of a node : 1- should they re-install couchbase and then go through the wizard for modifying such path Yes   2- is there another REST endpoint where they can invoke to un-provision a node Yes, somewhat. wget -O- -vvd --user=Administrator --password=asdasd --post-data="otpNode=zzzzForce" http://lh:9000/controller/ejectNode

MC Brown added a comment - 10/Dec/12 8:40 AM So do we want to document that to change the data path, you must: 1. Remove the node from the cluster 2. Update the data path through REST 3. Re-add the node to the cluster If so, I can add a suitable section to the end of the admin tasks section.

Farshid Ghods added a comment - 10/Dec/12 8:43 AM #2 > reset the node if node is still in a provisioned state after removing from the cluster. to reset the node you can use ejectNode api or reinstall couchbase #3. update the data path #4. re-add the node

Perry Krug added a comment - 12/Dec/12 8:20 AM FYI, you don't "need" to update the path via the REST API. The first page of the setup wizard lets you set the data path. So I would say the documentation should be: If you want to change the data path of an existing node, you should first rebalance it out of the cluster (making sure you follow these best practices so as not to reduce the capacity of your cluster and impact performance...in here we should have that the best practice is to always swap it with a new node, do we have that somewhere yet?) and then change the data path either using the web UI, the CLI or the REST API and add it back to the cluster with a rebalance.

MC Brown added a comment - 12/Dec/12 8:23 AM I'm adding a new section into the admin tasks based on this approach. Yes, we have best practice on not reducing node counts and swapping them out.

MC Brown added a comment - 12/Dec/12 11:07 AM Documentation has been updated with a new section with the recommended process: http://www.couchbase.com/docs/couchbase-manual-2.0/couchbase-admin-tasks-changepath.html