[ClusterLabs] 答复: 答复: 答复: 答复: How to configure to make each slave resource has one VIP

[范国腾]

Thanks Rorthais, Got it. The following command could make sure that it move to the master if there is no standby alive:

pcs constraint colocation add pgsql-ip-stby1 with slave pgsql-ha 100
pcs constraint colocation add pgsql-ip-stby1 with pgsql-ha 50

-----邮件原件-----
发件人: Jehan-Guillaume de Rorthais [mailto:jgdr at dalibo.com] 
发送时间: 2018年3月8日 17:41
收件人: 范国腾 <fanguoteng at highgo.com>
抄送: Cluster Labs - All topics related to open-source clustering welcomed <users at clusterlabs.org>
主题: Re: [ClusterLabs] 答复: 答复: 答复: How to configure to make each slave resource has one VIP

On Thu, 8 Mar 2018 01:45:43 +0000
范国腾 <fanguoteng at highgo.com> wrote:

> Sorry, Rorthais, I have thought that the link and the attachment was 
> the same document yesterday.

No problem.

For your information, I merged the draft in the official documentation yesterday.

> I just read the attachment and that is exactly what I ask originally.

Excellent! Glad it could helped.

> I have two questions on the following two command:
> # pcs constraint colocation add pgsql-ip-stby1 with slave pgsql-ha 10
> Q: Does the score 10 means that " move to the master if there is no 
> standby alive "?

Kind of. It actually says nothing about moving to the master. It just says the slaves IP should prefers to locate with a slave. If slaves nodes are down or in standby, the IP "can" move to the master as nothing forbid it.

In fact, while writing this sentence, I realize there's nothing to push the slaves IP on the master if other nodes are up, but the pgsql-ha slaves are stopped or banned. The configuration I provided is incomplete.

1. I added the missing constraints in the doc online 2. notice I raised all the scores so they are higher than the stickiness

See:
https://clusterlabs.github.io/PAF/CentOS-7-admin-cookbook.html#adding-ips-on-slaves-nodes

Sorry for this :/

> # pcs constraint order start pgsql-ha then start pgsql-ip-stby1 
> kind=Mandatory
> Q: I did not set the order and I did not find the issue until now. So 
> I add this constraint? What will happen if I miss it?

The IP address can start before PostgreSQL is up on the node. You will have client connexions being rejected with error "PostgreSQL is not listening on host [...]".

> Here is what I did now:
> pcs resource create pgsql-slave-ip1 ocf:heartbeat:IPaddr2 ip=192.168.199.186
>   nic=enp3s0f0 cidr_netmask=24 op monitor interval=10s; pcs resource 
> create pgsql-slave-ip2 ocf:heartbeat:IPaddr2 ip=192.168.199.187
>   nic=enp3s0f0 cidr_netmask=24 op monitor interval=10s; pcs constraint 
> colocation add pgsql-slave-ip1 with pgsql-ha

It misses the score and the role. Without role specification, it can colocates with Master or Slave with no preference.

> pcs constraint colocation add pgsql-slave-ip2 with pgsql-ha

Same, it misses the score and the role.

> pcs constraint colocation set pgsql-slave-ip1 pgsql-slave-ip2
>   pgsql-master-ip setoptions score=-1000

The score seems too high in  my opinion, compared to other ones.

You should probably remove all the colocation constraints and try with the one I pushed online.

Regards,

> -----邮件原件-----
> 发件人: Jehan-Guillaume de Rorthais [mailto:jgdr at dalibo.com]
> 发送时间: 2018年3月7日 16:29
> 收件人: 范国腾 <fanguoteng at highgo.com>
> 抄送: Cluster Labs - All topics related to open-source clustering 
> welcomed <users at clusterlabs.org> 主题: Re: [ClusterLabs] 答复: 答复: 答复: How 
> to configure to make each slave resource has one VIP
> 
> On Wed, 7 Mar 2018 01:27:16 +0000
> 范国腾 <fanguoteng at highgo.com> wrote:
> 
> > Thank you, Rorthais,
> > 
> > I read the link and it is very helpful.  
> 
> Did you read the draft I attached to the email? It was the main 
> purpose of my
> answer: helping you with IP on slaves. It seems to me your mail is 
> reporting different issues than the original subject.
> 
> > There are some issues that I have met when I installed the cluster.  
> 
> I suppose this is another subject and we should open a new thread with 
> the appropriate subject.
> 
> > 1. “pcs cluster stop” could not stop the cluster in some times.  
> 
> You would have to give some more details about the context where "pcs 
> cluster stop" timed out.
> 
> > 2. when I upgrade the PAF, I could just replace the pgsqlms file. 
> > When I upgrade the postgres, I just replace the /usr/local/pgsql/.
> 
> I believe both actions are documented with best practices in this 
> links I gave you.
> 
> > 3.  If the cluster does not stop normally, the pgcontroldata status 
> > is not "SHUTDOWN",then the PAF would not start the postgresql any 
> > more, so I normally change the pgsqlms as below after installing the PAF.
> > [...]
> 
> This should be discussed to understand the exact context before 
> considering your patch.
> 
> At a first glance, your patch seems quite dangerous as it bypass the 
> sanity checks.
> 
> Please, could you start a new thread with proper subject and add 
> extensive informations about this issue? You could open a new issue on 
> PAF repository as well: https://github.com/ClusterLabs/PAF/issues
> 
> Regards,



--
Jehan-Guillaume de Rorthais
Dalibo