[GENERAL] unsupported frontend protocol
I've painted myself into a little corner here: I pg_dumped a 7.4.3 database, created a database of the same name on a 7.3.4 server, psql'd into the new database, and \i'd the dump file. The database was created although there were a variety of errors which I realized were due to 7.4.3 and 7.3.4 SQL incompatibilities. I had also added a new entry to pg_hba.conf. After restarting the 7.3.4 postmaster I started getting an endless series of "FATAL: unsupported frontend protocol" messages, even when not using psql. The only other access to the cluster is by PHP 4.2.2, and nothing accesses the newly restored database. Since the db had errors anyway, I restored the old pg_hba.conf file, dropped the new database, and restarted the postmaster -- i.e. attempting to wipe out all changes. HOWEVER, the protocol error message persists, endlessly and infuriatingly! Searching on the error message text doesn't return anything enlightening. Can anyone suggest why this is happening or where I find a log with further details. Thank you in advance John Gunther ---(end of broadcast)--- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
Re: [GENERAL] unsupported frontend protocol
Agreed that the symptom fits a client library mismatch, but the only thing I moved from the 7.4.3 system to the 7.3.4 system was a pg_dump'ed database. That can't carry anything that would affect the interaction between the existing PHP 4.2.2 and PostgreSQL 7.3.4 versions, can it? They worked without error for many months prior to that database load. Is there any postmaster logging I can turn on that will detail what's triggering the error? John Tom Lane wrote: Not surprising if you are using 7.4 or later client libraries. Those will try to connect using the PG V3 protocol (added in 7.4). libpq, at least, will fall back to the older protocol if V3 doesn't work, but I am not sure whether PHP uses libpq. regards, tom lane ---(end of broadcast)--- TIP 7: don't forget to increase your free space map settings
Re: [GENERAL] unsupported frontend protocol
Connection logging shows an unvarying pattern: every connection attempt, regardless of target database or source (PHP or psql), first uses a wrong protocol and then succeeds on a second attempt, presumably after falling back: LOG: connection received: host=[local] FATAL: unsupported frontend protocol LOG: connection received: host=[local] LOG: connection authorized: user=testuser database=test Any thoughts on what could make both clients attempt wrong protocol? /usr/lib has the following libpq files: -rw-r--r-- 1 root root 592784 Jun 24 2004 /usr/lib/libpq.a lrwxrwxrwx 1 root root 12 Jul 8 2004 /usr/lib/libpq.so -> libpq.so.3.1 lrwxrwxrwx 1 root root 12 Nov 28 2003 /usr/lib/libpq.so.2 -> libpq.so.2.2 -rwxr-xr-x 1 root root 61252 Nov 4 2003 /usr/lib/libpq.so.2.2 lrwxrwxrwx 1 root root 12 Jul 8 2004 /usr/lib/libpq.so.3 -> libpq.so.3.1 -rwxr-xr-x 1 root root 112040 Jun 24 2004 /usr/lib/libpq.so.3.1 Tom Lane wrote: Bucks vs Bytes Inc <[EMAIL PROTECTED]> writes: Is there any postmaster logging I can turn on that will detail what's triggering the error? Well, you could change the error report in postmaster.c to show the specific protocol version code it's receiving (7.4 and up do this, but it hadn't occurred to us as of 7.3). I have little doubt what you will find though. Maybe what you really want is to enable log_connections so you can find out where the problematic connections are coming from. regards, tom lane
