when I run start.bat file of tomcat on linux with postgres database. It gives following error after changed in postgres_hba.conf file.
C3P0PooledConnectionPoolManager[identityToken->2u13c99u1fd86im176rze7|779becbd]-HelperThread-#1--WARN -com.mchange.v2.resourcepool.BasicResourcePool:com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask#1de8b573 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
org.postgresql.util.PSQLException: FATAL: remaining connection slots are reserved for non-replication superuser connections
The error message is fairly clear. You have tried to open more database connections than you have configured in postgresql.conf. Even the shortest search of your logs and the manuals would have made this clear.
Related
I am new to PostgreSQL and I am trying to set up a streaming replication from our server to a test DB on my laptop. I have been following this tutorial https://www.percona.com/blog/2018/09/07/setting-up-streaming-replication-postgresql/ along with the Postgres documentation here https://www.postgresql.org/docs/11/runtime-config-replication.html.
I'm running Windows 10, PostgreSQL 11, PostGIS 2.5 extension.
The server and my local machine both keep shutting down and the logs are filled with postmaster.pid errors such as:
LOG: performing immediate shutdown because data directory lock file is invalid
LOG: received immediate shutdown request
LOG: could not open file "postmaster.pid": No such file or directory
WARNING: terminating connection because of crash of another server process
DETAIL: The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.
Could anyone point me towards the issue here? I know my server's aren't configured properly but I just don't know what configurations need to be changed.
Here is an image of my standby server's most recent log.
standby log
Here is an image of my master server's most recent log.
master log
You must have messed up in many ways.
You removed or overwrote postmaster.pid on the master server.
That is very dangerous and causes the server to die with the error message you quote.
You didn't create recovery.conf before starting the standby server, or you removed backup_label. From the error messages I'd suspect the second, with ensuing data corruption.
When I try to login to the PostgreSQL database I get the error "FATAL: sorry, too many clients already". I checked the number of the connections from another already opened session with the sql select sum(numbackends) from pg_stat_database where datname = '$dbname';, the number is only 13. But the max_connections is set to 100. How can the error happen when the max_connections is not reached?
The PostgreSQL server is a read replica instance running in the Docker container. I've verified the max_connections value by running show max_connections;. Also, the error seems random to me because sometimes I tried to open as many connections as possible to test the limit and it can open 100 connections then throw the error after that.
It turns out the reason was that the IO was occupied fully and it was almost not responding. Then it threw the error "FATAL: sorry, too many clients already" despite the max connections was not reached.
I am getting FATAL: the database system is shutting down errors while creating PostgreSQL JDBC connections to a PostgreSQL 9.2 server. The specific exception path I'm getting from JDBC is here:
Caused by: org.postgresql.util.PSQLException: FATAL: the database system is shutting down
at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:398)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:173)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:64)
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:136)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:29)
at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:21)
at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:31)
at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
at org.postgresql.Driver.connect(Driver.java:267)
From various log files (from PostgreSQL, from our management layer, from the app using PostgreSQL), I do not see any database shutdown actually happening (other connections are created to PostgreSQL as usual, no shutdown was initiated from our management layer, etc.), however in the PostgreSQL server logs I do see the error message with the same timestamp:
2014-06-16 12:30:00.736 GMT LOG: connection received: host=127.0.0.1 port=38530
2014-06-16 12:30:00.737 GMT FATAL: the database system is shutting down
Researching online, I learned that this error message is used whenever PostgreSQL shuts down connections.
Why would PostgreSQL refuse to give me a new connection? Could this be caused by some sort of resource contention? How can I get more information about the error from PostgreSQL itself?
This issue turned out to be caused by a very bad misuse of PostgreSQL where our server had booted two PostgreSQL instances on the same data directory (it had deleted postmaster.pid and used a new port number, so the normal safeguards against this behavior were bypassed) which explains why the logs did not hold any useful information -- they were being overwritten by the PostgreSQL instance which wasn't refusing connections. The actual issue was caused by a complex interaction between the competing PostgreSQL instances, and I hope nobody else runs into this issue as well!
We encountered this problem when the server was restarted. In this case the reboot did not initiate the connection with PostgreSql. Just check the status: "/etc/init.d/postgresql status" if the return is: "no server running" just start: "/etc/init.d/postgresql start"
Maybe there is not enough space on hard drive.
SOLUTION:
brew remove postgresql
Temporary rename the lock files: mv /tmp/.s.PGSQL.5432.lock /tmp/BK.s.PGSQL.5432.lockand mv /tmp/.s.PGSQL.5432 /tmp/BK.s.PGSQL.5432
brew install postgresql
Enjoy!
We are using PostgreSQL Crane plan, and got a lot of log like this
app postgres - - [5-1] ... LOG: could not receive data from client: Connection reset by peer
We are using about 50 dynos.
Is PostgreSQL running out of connections with bunch of dynos?
Can someone help me explain this case?
Thanks
From what I've found the cause for the errors is the client not disconnecting at the end of the session, or a new connection not being created.
New connection solving the problem:
Postgres error on Heroku with Resque
Explicit disconnection solving the problem:
https://github.com/resque/resque/issues/367 (comment #2)
There's a Heroku FAQ entry on this: Understanding Heroku Postgres Log Statements and Common Errors: could not receive data from client: Connection reset by peer.
Although this log is emitted from postgres, the cause for the error has nothing to do with the database itself. Your application happened to crash while connected to postgres, and did not clean up its connection to the database. Postgres noticed that the client (your application) disappeared without ending the connection properly, and logged a message saying so.
If you are not seeing your application’s backtrace, you may need to ensure that you are, in fact, logging to stdout (instead of a file) and that you have stdout sync’d.
I'm trying to run a Drupal migration via SSH and drush (a command line shell), copying data from a postgres database to mysql.
It works fine for a while (~5 mins or so), but then I get the error:
SQLSTATE[HY000]: General error: 7 SSL [error] SYSCALL error: EOF detected
The postgres database connection seems to have gone, and I just get errors:
SQLSTATE[HY000]: General error: 7 no [error] connection to the server
It works fine locally, so I think the problem must be with postgres and running a script over SSH - but googling these errors returns nothing useful. Does anyone know what could be causing this?
Could be a timeout. first inspect the log (maybe change ssl_renegotiation_limit)
BTW: IIRC, the renegotiation does not take place after a fixed amount of time, but after a certain amount of transmitted characters (2GB?)
You should check both your PostgreSQL and MySQL logs for further potential details. If there's not much in the PostgreSQL log, look at the log_min_error_statement in postgresql.conf. As you'll find through that link, you can tune it to increase the amount of logging. If there's still not clues in the PostgreSQL log, I would look at other components in your system for the problem.