I can connect fine with PHP and locally using Psql, but Perl does not.
my $dbh = DBI->connect("DBI:Pg:dbname=mydb,host=localhost:5432","user","pass",{'RaiseError' => 1});
I believe the error is because my socket is in tmp:
postgres#host/opt/psql/bin $ netstat -an | grep 5432
tcp 0 0 0.0.0.0:5432 0.0.0.0:* LISTEN
tcp6 0 0 :::5432 :::* LISTEN
unix 2 [ ACC ] STREAM LISTENING 24728255 /tmp/.s.PGSQL.5432
unix 3 [ ] STREAM CONNECTED 24729004 /tmp/.s.PGSQL.5432
And when I run my simple perl script it seems to look in /var/run:
./test.pl
DBI connect('dbname=mydb','user',...) failed: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"? at ./test.pl line 6
I tried to simply create a symlink, but that doesn't seem to be working:
sudo ln -s /tmp/.s.PGSQL.5432 /var/run/postgresql/.s.PGSQL.5432
ln: failed to create symbolic link `/var/run/postgresql/.s.PGSQL.5432': No such file or directory
Some other simple stuff:
pg_hba.conf trusts all localhost connections as well as those of my subnet.
postgresql.conf has the following:
listen_addresses = '*'
See http://www.postgresql.org/docs/9.2/static/libpq-connect.html#LIBPQ-CONNECT-HOST:
host
Name of host to connect to. If this begins with a slash, it specifies
Unix-domain communication rather than TCP/IP communication; the value
is the name of the directory in which the socket file is stored. The
default behavior when host is not specified is to connect to a
Unix-domain socket in /tmp (or whatever socket directory was specified
when PostgreSQL was built). On machines without Unix-domain sockets,
the default is to connect to localhost.
So a connection string that has host=/tmp should make your Pg client look in the right place (which is supposed to be the default anyway).
Related
i actually use a dbeaver client which executes a pg_dump command
on a remote server. The command starts exactly like that :
pg_dump --verbose --host=127.0.0.1 --port=47855 --username=user-accounet..
i dont't know how dbeaver creates ssh tunnel (it uses a bastion)
but, it is not the question.
the question is : when i excute the command below..
lsof -i -P -n | grep pg_dump
i get this :
pg_dump 14144 parcss-alexco 3u IPv4 397966 0t0 TCP 127.0.0.1:35978->127.0.0.1:47855 (ESTABLISHED)
what is this adress ip : 35978 ?
what kind of binding 35978 --> 47855 means ?
Does it concern a remote ip adresse ? local ?
i'd like to understand..
A TCP connection is between to sockets. A fully specified socket has an IP address and a port number.
pg_dump uses port 47855 on 127.0.0.1 for the remote socket for the connection, but what about the socket on the other end? The IP address is clear, but what is the port number? Since the socket is not explicitly bound to a certain port with bind(2), connect(2) will assign an “ephemeral port” number. This happens to be 35978 in your case.
I have a Debian 9 machine with a PostgreSQL (PSQL) 9.6 server installed.
This PSQL server does not accept any connexion from other machines (only from itself).
I have been doing my best to work out this problem and I guess some of you will think this is a topic for a PostgreSQL forum, BUT let me explain :
I also have a Ubuntu 16.04 machin running also a PostgreSQL 9.5 server and I don't have this problem with it.
Other-than-PSQL connexions to both the Debian and the Ubuntu machines coming from other machines (ping, x2gp) work fine. Firewalls are deactivated.
The PSQL server rules for accepting connexions is based on a config file called pg_hba.conf. Its content on the Debian machine is :
# Database administrative login by Unix domain socket
local all postgres md5
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all md5
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all 192.168.1.0/24 md5
On the Ubuntu machine, the file is very similar :
# Database administrative login by Unix domain socket
local all postgres md5
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all md5
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all 192.168.1.0/24 md5
I also tried copying-pasting the config_file from the Ubuntu machine to the Debian one to see if it worked. It did not.
Of course, I don't forget restarting the PSQL server.
Now when I do a netstat -an | grep 5432 (PSQL server listens on port 5432), on the Debian machine, I get :
$ netstat -an | grep 5432
tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN
tcp6 0 0 ::1:5432 :::* LISTEN
unix 2 [ ACC ] STREAM LISTENING 15854569 /var/run/postgresql/.s.PGSQL.5432
From the little I understand about networks, this means indeed that the machine only listen on the 5432 port for localhost inbound connexions.
But when I do the same on the Ubuntu machine, I get :
$ netstat -an | grep 5432
tcp 0 0 0.0.0.0:5432 0.0.0.0:* LISTEN
tcp6 0 0 :::5432 :::* LISTEN
unix 2 [ ACC ] STREAM LISTENING 19472 /var/run/postgresql/.s.PGSQL.5432
which means, I believe, it listens to inbound connexions from any IP address.
But why ?
Why this difference in behaviour between the two machines ?
Look at your postgresql.conf, look for listen_addresses, you should have 0.0.0.0 for ipv4 and :: for ipv6.
Description -> https://www.postgresql.org/docs/9.1/static/runtime-config-connection.html
And, after my comment in your answer, I just noticed that the line
#listen_addresses = 'localhost'
started with a #.
I deleted it to un-comment the line so that it is operational and now it works.
Thanks !
I am, for the first time, attempting to set up an application on a remote/cloud VPS (I am using Digital Ocean if it matters). I am attempting to create an SSH tunnel from my client to the remote database. As this is not something I have attempted before, I referenced this, this, and this.
After looking over the articles, I ran the following on my client/local machine:
ssh -L 5433:localhost:5432 user#REMOTE_IP
then I tried to connect:
psql -h localhost -p 5433 postgres;
However, I receive the following error:
psql: could not connect to server: Connection refused
Is the server running on host "localhost" (127.0.0.1) and accepting
TCP/IP connections on port 5433?
To my knowledge, my pg_hba.conf (on the remote server) is the default:
# Database administrative login by Unix domain socket
local all postgres peer
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
I changed "listen_addresses" in postgresql.conf to *
# - Connection Settings -
listen_addresses = '*' # what IP address(es) to listen on;
# comma-separated list of addresses;
# defaults to 'localhost'; use '*' for all
# (change requires restart)
port = 5432 # (change requires restart)
max_connections = 100 # (change requires restart)
I also tried substituting 127.0.0.1 forlocalhost with no success.
Any advice would be appreciated; SSH tunnels and the like are not something I am familiar with.
Thanks.
EDIT:
Per #drdaeman excellent advice, I ran the following:
sudo ssh -N -vvv -L 5433:localhost:5432 user#host
The last few debug lines are as follows:
debug1: Local forwarding listening on 127.0.0.1 port 5433.
debug2: fd 5 setting O_NONBLOCK
debug3: fd 5 is O_NONBLOCK
debug1: channel 1: new [port listener]
debug2: fd 3 setting TCP_NODELAY
debug3: ssh_packet_set_tos: set IP_TOS 0x10
debug1: Requesting no-more-sessions#openssh.com
debug3: send packet: type 80
debug1: Entering interactive session.
debug1: pledge: network
debug3: receive packet: type 80
debug1: client_input_global_request: rtype hostkeys-00#openssh.com want_reply 0
Output from sudo netstat -ltpn | grep 5432
tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN 5835/postgres
It stops there, unresponsive to any commands.
Thanks for any direction.
Based on your description, everything looks OK to me - don't see where the problem is, but the commands you're running and your configuration looks correct. Here are the general steps you can take to diagnose the issue:
First, check if your PostgreSQL server is actually listening. On your server, run this:
$ sudo netstat -ltpn | grep 5432
(Or you can use ss -ltpn from iproute2 instead of older netstat)
If you don't see anything, it means no process is listening on tcp/5432. You can try to see if PostgreSQL is listening anywhere at all:
$ sudo netstat -lpn | grep postgre
If it doesn't - check whenever your server is actually running (depends on the OS and distribution, but check ps aux output first) and check your server logs (probably in /var/log) if you see any problems there.
Then, make sure you don't accidentally run psql on your server (when you SSH, it also opens the shell session unless you specify the -N flag). You need to run it on your local machine ;)
Then, you may also consider adding -v (or even -vvv) to your ssh command - it'll spew a lot of useful debug information, e.g. a normal operation looks like this:
debug1: Connection to port 5433 forwarding to localhost port 5432 requested.
debug1: channel 3: new [direct-tcpip]
debug1: channel 3: free: direct-tcpip: listening port 5433 for localhost port 5432, connect from ::1 port 60039 to ::1 port 5433, nchannels 4
If you see something like channel 3: open failed: connect failed: Connection refused instead, this means PostgreSQL had refused the connection - and you need to check its logs for the reasoning - possibly, after enabling log_connections and log_disconnections in the config (don't forget to reload the configuration).
I'm trying to create a tunnel to a remote server, using this command:
sudo ssh -i ~/.ssh/id_rsa -g -L 5433:remote-ip:5432 user#dbserver.com -v
So, the goal is to set up tunnel that listens on local port 5433 and redirects the request to dbserver.com:5432
I have Teampostgresql set up on my local machine and try to connect to the remote DB, using the tunnel.
When I set up the tunnel and try to connect, I can see the following message in the terminal window:
debug1: channel 3: free: direct-tcpip: listening port 5433 for 127.0.0.1 port 5432,
connect from 127.0.0.1 port 51893 to 127.0.0.1 port 5433, nchannels 5
Unfortunately, it's not working.
Any ideas what I'm doing wrong?
[Edit]
Changed the localhost to remote-host IP, as recommended by the first commenter (who, interestingly, deleted the comment)...
[Edit2]
As per request, the results from netstat -nlp | grep 5432
tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN -
unix 2 [ ACC ] STREAM LISTENS 15963 - /tmp/.s.PGSQL.5432
unix 2 [ ACC ] STREAM LISTENS 15961 - /var/run/postgresql/.s.PGSQL.5432
Please read before replying it as duplicate (as it perhaps can happen). I am running my postmaster (postgres) server. See below for 'sudo netstat -anp|grep 5432' output?
tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN 29606/postmaster
unix 2 [ ACC ] STREAM LISTENING 1650581 29606/postmaster /var/run/postgresql/.s.PGSQL.5432
unix 2 [ ACC ] STREAM LISTENING 1650582 29606/postmaster /tmp/.s.PGSQL.5432
I am able to connect from localhost using
psql -h localhost (OR 127.0.0.1) -d <DB> -U user -W
But when I try to connect from other hosts using tcp, by specifying
psql -h ip_add_postmaster -d <DB> -U user -W
It throws:
psql: could not connect to server: Connection refused
Is the server running on host XXXXXX and accepting TCP/IP connections on port 5432?
What's wrong here?
pg_hba.conf
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
In postgresql.conf,
listen_addresses = 'localhost, 127.0.0.1, ip_add_postmaster'
Note: ip_add_postmaster is same as my Elastic IP and not public DNS. If this information
matters.
What am I doing wrong here? Machine is hosted on Amazon EC2 and have open the port 5432.
As your netstat output indicates, it's listening at 127.0.0.1:5432 which is localhost. That is only connectable from localhost ;)
Set listen_addresses='*' in your config and it will work.
[edit]
Other things to check:
is the amazon firewall blocking anything?
is iptables blocking anything?
But first make sure the listening address is correct, your netstat output shows that it won't work like this.
listen_addresses='localhost, private_ip' fixed the issue. I was not able to start postmaster server on elastic IPs. Once postgres server started o localhost and private IPs, I was able to connect.
One other issue I have found was if you end up with two Postgres installations, the second one can choose non-default port (in my case it was 5433 i/o 5432). So checking the port in postgresql.conf might be a good idea.
I ran into this issue and tried all sorts of fixes I found across SO, and want to add a simple solution that worked for me after realizing it had to do with permissions in my case.
Simply, if you're running a psql server on Windows, you are initially restricted to the default postgres superuser for logging in, launching the server, and so on.
So, first try running from the command line:
psql -U postgres -h localhost -p 5432
and enter your password at the prompt. If you've managed to login and the server is up, then it was a permissions issues. From here, you can create a role for yourself that has login privileges to whatever database you are trying to run.
If the error persists, then consider checking postgresql.conf as mentioned above, to make sure default IP is set to * or localhost, and the port set to 5432 or whatever port you want as default.
I also ran into the same issue. On debugging, it was nothing related to the port, but due to some missing directories in the Postgres folder.
While updating Mac OS (from 10.13.1 -> 10.13.13), some folders in the directory /usr/local/var/postgres/ gets deleted. The fix was the adding the missing directories:
mkdir /usr/local/var/postgres/pg_tblspc
mkdir /usr/local/var/postgres/pg_twophase
mkdir /usr/local/var/postgres/pg_stat
mkdir /usr/local/var/postgres/pg_stat_tmp
mkdir /usr/local/var/postgres/pg_replslot
mkdir /usr/local/var/postgres/pg_snapshots
mkdir /usr/local/var/postgres/pg_logical/{snapshots,mappings}