Re: Rebuilding AAE hashes - small question
Date: Thu, 10 Apr 2014 14:42:23 +0100 From: Guido Medina guido.med...@temetra.com To: Engel Sanchez en...@basho.com, Luke Bakken lbak...@basho.com Cc: riak-users riak-users@lists.basho.com Subject: Re: Rebuilding AAE hashes - small question Message-ID: 53469fbf.1000...@temetra.com Content-Type: text/plain; charset=iso-8859-1; Format=flowed Thanks Engel, That approach looks very accurate, I would only suggest to have a riak-admin cluster stop-aae and similar for start, for the dummies ;-) I agree with Guido that would be the best solution for the dummies. But a good interim solution would be if Basho puts up a “definitive guide to enabling and disabling AAE” somewhere. I have now seen a lot of different commands to achieve this. In this thread and in the “RIAK 1.4.6 - Mass key deletion” thread and some older threads. There is the per-host approach and there seem to be several cluster-wide / rpc approaches. I have seen: a. rpc:multicall(riak_kv_entropy_manager, disable, []). rpc:multicall(riak_kv_entropy_manager, cancel_exchanges, []). z. (with questions about the a. and z. ) and there is: riak_core_util:rpc_every_member_ann(riak_kv_entropy_manager, disable, [], 6). And similar to enable. Can someone please advise what is the “authoritative” way to enable/disable AAE? Kind regards, Timo ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Re: Rebuilding AAE hashes - small question
Hey there. There are a couple of things to keep in mind when deleting invalid AAE trees from the 1.4.3-1.4.7 series after upgrading to 1.4.8: * If AAE is disabled, you don't have to stop the node to delete the data in the anti_entropy directories * If AAE is enabled, deleting the AAE data in a rolling manner may trigger an avalanche of read repairs between nodes with the bad trees and nodes with good trees as the data seems to diverge. If your nodes are already up, with AAE enabled and with old incorrect trees in the mix, there is a better way. You can dynamically disable AAE with some console commands. At that point, without stopping the nodes, you can delete all AAE data across the cluster. At a convenient time, re-enable AAE. I say convenient because all trees will start to rebuild, and that can be problematic in an overloaded cluster. Doing this over the weekend might be a good idea unless your cluster can take the extra load. To dynamically disable AAE from the Riak console, you can run this command: riak_core_util:rpc_every_member_ann(riak_kv_entropy_manager, disable, [], 6). and enable with the similar: riak_core_util:rpc_every_member_ann(riak_kv_entropy_manager, enable, [], 6). That last number is just a timeout for the RPC operation. I hope this saves you some extra load on your clusters. On Wed, Apr 9, 2014 at 11:02 AM, Luke Bakken lbak...@basho.com wrote: Hi Guido, I specifically meant riak-admin transfers however using riak-admin wait-for-service riak_kv riak@node is a good first step before waiting for transfers. Thanks! -- Luke Bakken CSE lbak...@basho.com On Wed, Apr 9, 2014 at 7:54 AM, Guido Medina guido.med...@temetra.comwrote: What do you mean by wait for handoff to finish? Are you referring to wait for the service to be fully started? i.e. riak-admin wait-for-service riak_kv riak@node Or do you mean to check for riak-admin transfers on the started node and wait until those handoffs/transfers are gone? Guido. On 09/04/14 15:46, Luke Bakken wrote: Hi Guido, That is the correct process. Be sure to use the rolling restart procedure when restarting nodes (i.e. wait for handoff to finish before moving on). -- Luke Bakken CSE lbak...@basho.com On Wed, Apr 9, 2014 at 6:34 AM, Guido Medina guido.med...@temetra.comwrote: Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Re: Rebuilding AAE hashes - small question
Thanks Engel, That approach looks very accurate, I would only suggest to have a riak-admin cluster stop-aae and similar for start, for the dummies ;-) Guido. On 10/04/14 14:22, Engel Sanchez wrote: Hey there. There are a couple of things to keep in mind when deleting invalid AAE trees from the 1.4.3-1.4.7 series after upgrading to 1.4.8: * If AAE is disabled, you don't have to stop the node to delete the data in the anti_entropy directories * If AAE is enabled, deleting the AAE data in a rolling manner may trigger an avalanche of read repairs between nodes with the bad trees and nodes with good trees as the data seems to diverge. If your nodes are already up, with AAE enabled and with old incorrect trees in the mix, there is a better way. You can dynamically disable AAE with some console commands. At that point, without stopping the nodes, you can delete all AAE data across the cluster. At a convenient time, re-enable AAE. I say convenient because all trees will start to rebuild, and that can be problematic in an overloaded cluster. Doing this over the weekend might be a good idea unless your cluster can take the extra load. To dynamically disable AAE from the Riak console, you can run this command: riak_core_util:rpc_every_member_ann(riak_kv_entropy_manager, disable, [], 6). and enable with the similar: riak_core_util:rpc_every_member_ann(riak_kv_entropy_manager, enable, [], 6). That last number is just a timeout for the RPC operation. I hope this saves you some extra load on your clusters. On Wed, Apr 9, 2014 at 11:02 AM, Luke Bakken lbak...@basho.com mailto:lbak...@basho.com wrote: Hi Guido, I specifically meant riak-admin transfers however using riak-admin wait-for-service riak_kv riak@node is a good first step before waiting for transfers. Thanks! -- Luke Bakken CSE lbak...@basho.com mailto:lbak...@basho.com On Wed, Apr 9, 2014 at 7:54 AM, Guido Medina guido.med...@temetra.com mailto:guido.med...@temetra.com wrote: What do you mean by wait for handoff to finish? Are you referring to wait for the service to be fully started? i.e. riak-admin wait-for-service riak_kv riak@node Or do you mean to check for riak-admin transfers on the started node and wait until those handoffs/transfers are gone? Guido. On 09/04/14 15:46, Luke Bakken wrote: Hi Guido, That is the correct process. Be sure to use the rolling restart procedure when restarting nodes (i.e. wait for handoff to finish before moving on). -- Luke Bakken CSE lbak...@basho.com mailto:lbak...@basho.com On Wed, Apr 9, 2014 at 6:34 AM, Guido Medina guido.med...@temetra.com mailto:guido.med...@temetra.com wrote: Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com mailto:riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com mailto:riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com mailto:riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Rebuilding AAE hashes - small question
Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Re: Rebuilding AAE hashes - small question
Hi Guido, That is the correct process. Be sure to use the rolling restart procedure when restarting nodes (i.e. wait for handoff to finish before moving on). -- Luke Bakken CSE lbak...@basho.com On Wed, Apr 9, 2014 at 6:34 AM, Guido Medina guido.med...@temetra.comwrote: Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Re: Rebuilding AAE hashes - small question
What do you mean by wait for handoff to finish? Are you referring to wait for the service to be fully started? i.e. riak-admin wait-for-service riak_kv riak@node Or do you mean to check for riak-admin transfers on the started node and wait until those handoffs/transfers are gone? Guido. On 09/04/14 15:46, Luke Bakken wrote: Hi Guido, That is the correct process. Be sure to use the rolling restart procedure when restarting nodes (i.e. wait for handoff to finish before moving on). -- Luke Bakken CSE lbak...@basho.com mailto:lbak...@basho.com On Wed, Apr 9, 2014 at 6:34 AM, Guido Medina guido.med...@temetra.com mailto:guido.med...@temetra.com wrote: Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com mailto:riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Re: Rebuilding AAE hashes - small question
Hi Guido, I specifically meant riak-admin transfers however using riak-admin wait-for-service riak_kv riak@node is a good first step before waiting for transfers. Thanks! -- Luke Bakken CSE lbak...@basho.com On Wed, Apr 9, 2014 at 7:54 AM, Guido Medina guido.med...@temetra.comwrote: What do you mean by wait for handoff to finish? Are you referring to wait for the service to be fully started? i.e. riak-admin wait-for-service riak_kv riak@node Or do you mean to check for riak-admin transfers on the started node and wait until those handoffs/transfers are gone? Guido. On 09/04/14 15:46, Luke Bakken wrote: Hi Guido, That is the correct process. Be sure to use the rolling restart procedure when restarting nodes (i.e. wait for handoff to finish before moving on). -- Luke Bakken CSE lbak...@basho.com On Wed, Apr 9, 2014 at 6:34 AM, Guido Medina guido.med...@temetra.comwrote: Hi, If nodes are already upgraded to 1.4.8 (and they went all the way from 1.4.0 to 1.4.8 including AAE buggy versions) Will the following command (as root) on Ubuntu Servers 12.04: riak stop; rm -Rf /var/lib/riak/anti_entropy/*; riak start executed on each node be enough to rebuild AAE hashes? Regards, Guido. ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com ___ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
