PostgreSQL Guard

On Tue, Feb 27, 2024 at 3:43 AM Jason Long <hack3rcon@yahoo.com> wrote:

Hello,
I have some questions about the PostgreSQL database:

1- If I want to distribute the PostgreSQL database on several servers at
the same time. what should I do? Something similar to high availability.

HA replication is native in Postgresql.

2- Is there any special guard to protect PostgreSQL?

Guard, as in protection from a split-brain?

Hi,1- Both split-brain protection and security. Any tool?

2- Consider a database related to a website, which data is regularly entered. Now you want to transfer this database to another server. What's the solution?

On Tue, Feb 27, 2024 at 5:39 PM, Ron Johnson<ronljohnsonjr@gmail.com> wrote: On Tue, Feb 27, 2024 at 3:43 AM Jason Long <hack3rcon@yahoo.com> wrote:

Hello,
I have some questions about the PostgreSQL database:

1- If I want to distribute the PostgreSQL database on several servers at the same time. what should I do? Something similar to high availability.

HA replication is native in Postgresql. 

2- Is there any special guard to protect PostgreSQL?

Guard, as in protection from a split-brain? 

On 2/27/24 07:08, Jason Long wrote:

Hi,
1- Both split-brain protection and security. Any tool?

2- Consider a database related to a website, which data is regularly
entered. Now you want to transfer this database to another server.
What's the solution?

https://www.postgresql.org/docs/current/high-availability.html

--
Adrian Klaver
adrian.klaver@aklaver.com

Hi,Should I read https://www.postgresql.org/docs/current/warm-standby.html#STANDBY-SERVER-SETUP for question number 2?

On Tue, Feb 27, 2024 at 7:28 PM, Adrian Klaver<adrian.klaver@aklaver.com> wrote: On 2/27/24 07:08, Jason Long wrote:

Hi,
1- Both split-brain protection and security. Any tool?

2- Consider a database related to a website, which data is regularly
entered. Now you want to transfer this database to another server.
What's the solution?

https://www.postgresql.org/docs/current/high-availability.html

--
Adrian Klaver
adrian.klaver@aklaver.com

I used this web page to implement hot standby via physical streaming. This
command sets up everything for you:
pg_basebackup \
--pgdata=$PGDATA \
--dbname=service=basebackup \
--verbose --progress \
--checkpoint=fast \
--write-recovery-conf \
--wal-method=stream \
--create-slot --slot=pgstandby1 \
--compress=server-zstd
I got it from
https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/,
which I encourage you to read.

For guarding, and situations with a minimal RTO SLA, I use PgPool-II to
manage the cluster, automatic failover and Virtual IP address. Note that
only two database servers are needed. Install PgPool on the two DB
servers, and a third, smaller system.

There are other products which do the same thing as PgPool, and you might
find them better.

On Tue, Feb 27, 2024 at 12:00 PM Jason Long <hack3rcon@yahoo.com> wrote:

You may need to expand on / rephrase question 2.

Hi,Do I have to run this command on the server where the main database is located?

Suppose you want to transfer the database of a website like Amazon.com to a new server and delete the old one. Many users are buying and selling on this website at the same time and it is not possible to turn off the server. What do you do to move a database to another server?

On Tue, Feb 27, 2024 at 9:30 PM, Ron Johnson<ronljohnsonjr@gmail.com> wrote: I used this web page to implement hot standby via physical streaming.  This command sets up everything for you:pg_basebackup \
            --pgdata=$PGDATA \
            --dbname=service=basebackup \
            --verbose --progress \
            --checkpoint=fast \
            --write-recovery-conf \
            --wal-method=stream \
            --create-slot --slot=pgstandby1 \
            --compress=server-zstd
I got it from https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/, which I encourage you to read.
For guarding, and situations with a minimal RTO SLA, I use PgPool-II to manage the cluster, automatic failover and Virtual IP address.  Note that only two database servers are needed.  Install PgPool on the two DB servers, and a third, smaller system.
There are other products which do the same thing as PgPool, and you might find them better.
On Tue, Feb 27, 2024 at 12:00 PM Jason Long <hack3rcon@yahoo.com> wrote:

Hi,Should I read https://www.postgresql.org/docs/current/warm-standby.html#STANDBY-SERVER-SETUP for question number 2?

On Tue, Feb 27, 2024 at 7:28 PM, Adrian Klaver<adrian.klaver@aklaver.com> wrote: On 2/27/24 07:08, Jason Long wrote:

Hi,
1- Both split-brain protection and security. Any tool?

2- Consider a database related to a website, which data is regularly
entered. Now you want to transfer this database to another server.
What's the solution?

https://www.postgresql.org/docs/current/high-availability.html

--
Adrian Klaver
adrian.klaver@aklaver.com

As before, I encourage you to read
https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/
.

On Tue, Feb 27, 2024 at 3:48 PM Jason Long <hack3rcon@yahoo.com> wrote:

On Tue, Feb 27, 2024 at 3:48 PM Jason Long <hack3rcon@yahoo.com> wrote:

Suppose you want to transfer the database of a website like Amazon.com to
a new server and delete the old one. Many users are buying and selling on
this website at the same time and it is not possible to turn off the
server. What do you do to move a database to another server?

If we assume your question is "how can we migrate to a new system while
keeping the old one up and running to minimize downtime?" the answer is
logical replication.

https://www.crunchydata.com/blog/data-to-go-postgres-logical-replication

Cheers,
Greg

Hi,Thanks again.I have another questions:
1- Should I just install PostgreSQL normally on the Standby server?
2- Are the steps the same for other Linux distributions like Debian?

On Wed, Feb 28, 2024 at 9:29 AM, Ron Johnson<ronljohnsonjr@gmail.com> wrote: As before, I encourage you to read https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/.
On Tue, Feb 27, 2024 at 3:48 PM Jason Long <hack3rcon@yahoo.com> wrote:

Hi,Do I have to run this command on the server where the main database is located?

Suppose you want to transfer the database of a website like Amazon.com to a new server and delete the old one. Many users are buying and selling on this website at the same time and it is not possible to turn off the server. What do you do to move a database to another server?

On Tue, Feb 27, 2024 at 9:30 PM, Ron Johnson<ronljohnsonjr@gmail.com> wrote: I used this web page to implement hot standby via physical streaming.  This command sets up everything for you:pg_basebackup \
            --pgdata=$PGDATA \
            --dbname=service=basebackup \
            --verbose --progress \
            --checkpoint=fast \
            --write-recovery-conf \
            --wal-method=stream \
            --create-slot --slot=pgstandby1 \
            --compress=server-zstd
I got it from https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/, which I encourage you to read.
For guarding, and situations with a minimal RTO SLA, I use PgPool-II to manage the cluster, automatic failover and Virtual IP address.  Note that only two database servers are needed.  Install PgPool on the two DB servers, and a third, smaller system.
There are other products which do the same thing as PgPool, and you might find them better.
On Tue, Feb 27, 2024 at 12:00 PM Jason Long <hack3rcon@yahoo.com> wrote:

Hi,Should I read https://www.postgresql.org/docs/current/warm-standby.html#STANDBY-SERVER-SETUP for question number 2?

On Tue, Feb 27, 2024 at 7:28 PM, Adrian Klaver<adrian.klaver@aklaver.com> wrote: On 2/27/24 07:08, Jason Long wrote:

Hi,
1- Both split-brain protection and security. Any tool?

2- Consider a database related to a website, which data is regularly
entered. Now you want to transfer this database to another server.
What's the solution?

https://www.postgresql.org/docs/current/high-availability.html

--
Adrian Klaver
adrian.klaver@aklaver.com

Read
https://www.tecmint.com/configure-postgresql-streaming-replication-in-centos-8/
.

On Wed, Feb 28, 2024 at 10:36 AM Jason Long <hack3rcon@yahoo.com> wrote: