Обсуждение: Is it possible to replicate through an http proxy?
Hi all,
for a project we are working on we have the following requirements:
* PostgreSQL server on cloud
* Lot of edge devices that need access to DB
* Edges will only execute SELECT queries. No modification allowed on them.
* Internet access on edges can be lost and data must be accessible while connection is reestablished.
Our first approach to solve this was to setup a postgreSQL server on each edge and configure a logical replication from cloud server. This way our clients always connect to local server who automatically syncs with cloud server while Internet connection is up and also automatically reconnects when Internet connection is recovered after connection lost.
However, we facing a new requirement that we do not know how to solve. This requirement is that access to Internet from edge devices must be done through a http proxy server. Reading documentation we have not been able to find a way to create a replication with this limitation. The questions we would like to ask are:
* Is it possible to create a logical replication with this limitation?
* Is there an alternative solution to our problem bearing in mind this limitation?
Thank you very much!
Another solution to the problem instead of logical replication would be utilize wal_shipping and have the edge servers replay the wal using the restore_command
The wal files can be downloaded from from HTTP server via a proxy and placed on the edge servers wal_archive directory to be replayed
see
and
this is twisting the warm_standby and restore functions into odd shapes This gives up the fine control that logical replication provides and its not as seamless
On Tue, Jan 14, 2020 at 7:48 AM Iban Rodriguez <irodbar@gmail.com> wrote:
Hi all,for a project we are working on we have the following requirements:* PostgreSQL server on cloud* Lot of edge devices that need access to DB* Edges will only execute SELECT queries. No modification allowed on them.* Internet access on edges can be lost and data must be accessible while connection is reestablished.Our first approach to solve this was to setup a postgreSQL server on each edge and configure a logical replication from cloud server. This way our clients always connect to local server who automatically syncs with cloud server while Internet connection is up and also automatically reconnects when Internet connection is recovered after connection lost.However, we facing a new requirement that we do not know how to solve. This requirement is that access to Internet from edge devices must be done through a http proxy server. Reading documentation we have not been able to find a way to create a replication with this limitation. The questions we would like to ask are:* Is it possible to create a logical replication with this limitation?* Is there an alternative solution to our problem bearing in mind this limitation?Thank you very much!