database high availability
Hi everybody, Do anyone have any practical experience with multi master (active/active) database cluster for CloudStack? If yes, what is best practices and suggestions? BTW, what is cloudstack-mysql-ha-xxx.rpm? How can I use it? It seems that there is no official document for it. Regards, Alireza
Re: database high availability question vs haproxy
Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić -- Andrija Panić -- Andrija Panić
Re: database high availability question vs haproxy
Thanks Simon - that is what I thought... So my question would be then, haproxy vs native ACS/mysql connector going to galera1/galera2/etc...will figure out, for now we use haproxy for mysql/galera loadbalancing... THanks a lot Simon, Andrija On 5 June 2015 at 15:18, Simon Weller swel...@ena.com wrote: Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić -- Andrija Panić -- Andrija Panić -- Andrija Panić
Re: database high availability question vs haproxy
Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić -- Andrija Panić -- Andrija Panić
Re: database high availability question vs haproxy
Exactly...thanks Simon for the time and help :) Is there any mysql timeout/retry parameter that is set in db.properties (like db.cloud.queriesBeforeRetryMaster=5000), but I'm wondering since I'm using keepalived/haproxy setup, it takes up to 5-6 sec for keepalive to detect haproxy is down (while testing I shutdown haproxu on active node), and then keepalvied moves IP to another node - meaning I have 5-6sec of no connection between ACS mgmt servers and database/haproxy. Is this timeout configurabile on ACS/mysql connector side ? Thanks again, Andrija On 5 June 2015 at 15:54, Simon Weller swel...@ena.com wrote: I think haproxy is a better design in my opinion. You're going to have to use haproxy to balance the host agents to multiple management servers anyway, so you'll already be using it. haproxy can then manage the health checks to Galera rather than over complicating it with the CS Management configuration. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 8:37 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Thanks Simon - that is what I thought... So my question would be then, haproxy vs native ACS/mysql connector going to galera1/galera2/etc...will figure out, for now we use haproxy for mysql/galera loadbalancing... THanks a lot Simon, Andrija On 5 June 2015 at 15:18, Simon Weller swel...@ena.com wrote: Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared
Re: database high availability question vs haproxy
I'm not sure whether that's configurable and I haven't seen any examples out there that point to it being configurable. Having said that, there are people a lot more familiar with that than I am on the list. One option you do have for this particular failure situation, is to use monit to monitor the pid of the CS management service and if it's not running, force it to start up again. Losing a load balancer completely is very rare, so it's not likely to happen often at all. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 9:07 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Exactly...thanks Simon for the time and help :) Is there any mysql timeout/retry parameter that is set in db.properties (like db.cloud.queriesBeforeRetryMaster=5000), but I'm wondering since I'm using keepalived/haproxy setup, it takes up to 5-6 sec for keepalive to detect haproxy is down (while testing I shutdown haproxu on active node), and then keepalvied moves IP to another node - meaning I have 5-6sec of no connection between ACS mgmt servers and database/haproxy. Is this timeout configurabile on ACS/mysql connector side ? Thanks again, Andrija On 5 June 2015 at 15:54, Simon Weller swel...@ena.com wrote: I think haproxy is a better design in my opinion. You're going to have to use haproxy to balance the host agents to multiple management servers anyway, so you'll already be using it. haproxy can then manage the health checks to Galera rather than over complicating it with the CS Management configuration. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 8:37 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Thanks Simon - that is what I thought... So my question would be then, haproxy vs native ACS/mysql connector going to galera1/galera2/etc...will figure out, for now we use haproxy for mysql/galera loadbalancing... THanks a lot Simon, Andrija On 5 June 2015 at 15:18, Simon Weller swel...@ena.com wrote: Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly
Re: database high availability question vs haproxy
I think haproxy is a better design in my opinion. You're going to have to use haproxy to balance the host agents to multiple management servers anyway, so you'll already be using it. haproxy can then manage the health checks to Galera rather than over complicating it with the CS Management configuration. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 8:37 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Thanks Simon - that is what I thought... So my question would be then, haproxy vs native ACS/mysql connector going to galera1/galera2/etc...will figure out, for now we use haproxy for mysql/galera loadbalancing... THanks a lot Simon, Andrija On 5 June 2015 at 15:18, Simon Weller swel...@ena.com wrote: Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić -- Andrija Panić -- Andrija Panić -- Andrija Panić
Re: database high availability question vs haproxy
True..Thanks Simon... On 5 June 2015 at 16:28, Simon Weller swel...@ena.com wrote: I'm not sure whether that's configurable and I haven't seen any examples out there that point to it being configurable. Having said that, there are people a lot more familiar with that than I am on the list. One option you do have for this particular failure situation, is to use monit to monitor the pid of the CS management service and if it's not running, force it to start up again. Losing a load balancer completely is very rare, so it's not likely to happen often at all. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 9:07 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Exactly...thanks Simon for the time and help :) Is there any mysql timeout/retry parameter that is set in db.properties (like db.cloud.queriesBeforeRetryMaster=5000), but I'm wondering since I'm using keepalived/haproxy setup, it takes up to 5-6 sec for keepalive to detect haproxy is down (while testing I shutdown haproxu on active node), and then keepalvied moves IP to another node - meaning I have 5-6sec of no connection between ACS mgmt servers and database/haproxy. Is this timeout configurabile on ACS/mysql connector side ? Thanks again, Andrija On 5 June 2015 at 15:54, Simon Weller swel...@ena.com wrote: I think haproxy is a better design in my opinion. You're going to have to use haproxy to balance the host agents to multiple management servers anyway, so you'll already be using it. haproxy can then manage the health checks to Galera rather than over complicating it with the CS Management configuration. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 8:37 AM To: us...@cloudstack.apache.org Cc: dev@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Thanks Simon - that is what I thought... So my question would be then, haproxy vs native ACS/mysql connector going to galera1/galera2/etc...will figure out, for now we use haproxy for mysql/galera loadbalancing... THanks a lot Simon, Andrija On 5 June 2015 at 15:18, Simon Weller swel...@ena.com wrote: Personally, I think that Gallera is always going to be a safer option, as it handles conflict resolution natively. Having said that, it appears care has been taken in designing the ACS MGMT DB integration so that the chance of conflicts is very low. Galera requires a 3 nodes minimum, so it's a lot of hardware unless you've got plans to use it elsewhere in your organisation. The downside to Galera, is that it's synchronous replication, so it needs very low latency between nodes. That doesn't make it a good candidate for geographic separation between DB nodes for a DR scenario. You're understanding of the replication structure, as based on the design document is correct. MySQL (or Galera) handles all the replication. ACS just handles which node it's writing and reading from. In a 2 node native MySQL cluster, it's expected that you are setup for cross master-master replication. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Friday, June 5, 2015 2:41 AM To: dev@cloudstack.apache.org Cc: us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Hi Simon, thanks for the link - actually I have already read this - but Im still seaking for some answeres :) : - real world experience with DB HA in general - is i better to use haproxy(clustered/redudant) for mysql towards Galera cluster - or simply to reference 2 nodes (1 as master, another as slave) with native ACS DB HA - silly question but anyway... - my understanding - ACS just pings and connects to master or slave (all replication etc, is done from my side, not from ACS) ? Thanks again and any info is greatly appreciated. Andrija On 4 June 2015 at 16:23, Simon Weller swel...@ena.com wrote: Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have
Re: database high availability question vs haproxy
Andrija, Here is the original design document, and it should give you a better idea of what is implemented today: https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=34838207 We have plans to test this in our lab soon, but just haven't got around to it yet. - Si From: Andrija Panic andrija.pa...@gmail.com Sent: Thursday, June 4, 2015 9:08 AM To: dev@cloudstack.apache.org; us...@cloudstack.apache.org Subject: Re: database high availability question vs haproxy Anyone :) ? On 31 May 2015 at 00:26, Andrija Panic andrija.pa...@gmail.com wrote: Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić -- Andrija Panić
database high availability question vs haproxy
Hi, I would have a question on database HA feature in db.properties ( http://cloudstack-administration.readthedocs.org/en/latest/reliability.html#configuring-database-high-availability ) If I understand correctly, it is up to the admin to provide appropriate mysql HA (active-active, galera, etc) and ACS management server will JUST try to connect to slaves if the master is down ? We are running Galera, with haproxy/keepalived, and by using stoping haproxy, it takes i.e. 6sec for keepalived to detect haproxy is down, and failover IP to another host. During these 6 seconds, ACS managemnt server goes dead, because of this DB unavailability. So my wondering, is better to use ACS db HA feature, instead of loadbalancer for this specific purpose ? (we are also using haproxy/keepalived for management server loadbalancing - 2 servers in backend...) Any experience shared is really appreciated ! -- Andrija Panić
