Is it possible to provide write permissions for slave/standby servers in postgresql in a cluster? -

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i have 2 servers on same network have live streaming master-slave structure. i'm not using tools slony or bucardo. it's simple replication process can accomplished changing parameters in .conf files. curently can accept read/write on master , read-only on slave. want master-master structure, wherein both servers can accept read write requests. possible in postgresql 9.3 or above?

is possible provide write permissions slave/standby servers in postgresql

no.

it's simple replication process can accomplished changing parameters in .conf files

so, postgresql's built-in streaming replication.

however want master-master structure, wherein both servers can accept read write requests. possible in postgresql 9.3 or above?

there's extension postgresql 9.4 adds multi-master, called bdr. see http://bdr-project.org/docs/stable/ , http://2ndquadrant.com/bdr . it's not ready widespread adoption new database users though - should pretty confident postgresql , replication if you're going use @ point. (note: i'm 1 of developers of bdr). bdr asynchronous multi-master replication, it's not transparent clustering can point existing app @ , expect work without changes. see manual details.

there postgres-xc , fork postgres-xl, add tightly coupled multi-master clustering , parallel dispatch postgresql. apps may require fewer changes run on xc, requires fast, reliably, low-latency networking between nodes.

there other options multi-master variant of slony-i, bucardo project, etc.

all of these share common details: it's really, important know you're doing , exact limitations, caveats , special cases multi-master implementation have chosen are. if go ahead , deploy app pointing @ multiple masters without careful thought , testing going have sleepless weekends , angry users.

that's before disaster recovery planning, failover, backup management, etc.

if not know absolutely need multi-master, not use it.


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