Once we have checked out archives and our system views, we are ready to check for system processes. Checking for system processes might look a little crude but it has proven to be highly effective.
On the master, we can simply check for a process called wal_sender
. On the slave, we have to check for a process called wal_receiver
.
Let us check what we are supposed to see on the master first:
9314 ?? Ss 0:00.00 postgres: wal sender process hs ::1(61498) idle
On Linux we can see that the process does not only carry its purpose (in this case, wal_sender
) but also the name of the end user as well as network-related information. In our case we can see that somebody has connected from localhost through port 61498
.
The situation on the slave is pretty simple as well:
9313 ?? Ss 0:00.00 postgres: wal receiver process
All we see is a process, informing us that we are consuming XLOG.
If both processes are here, you have got a pretty good indicator already that your replication setup is working nicely.
18.118.37.254