unknown log messages

Hi,
I'm getting the following error in my log file. Normally it's every 10 minutes, but occasionally the frequency changes to 5min, 3,1,30sec, 10sec, 5sec and then every second. Weeks ago it took the db down with a disk full situation, but usually it clears after a few minutes of continuous errors.

Can anybody offer any thoughts for how to identify what this is, and how to correct the issue.
Thanks
Doug

Env: Greenplum 3.3.6(based on PG 8.2.13), Solaris 10u5, Sun X4540 (x86)
We are probing the machine with sitescope for cpu/mem/disk stats, but I don't believe it's connecting to the db.

2011-01-01 13:01:56.848368 CST,"root","root",p427,th1,"[local]",,2011-01-01 13:01:56 CST,0,,,seg-1,,,,,"FATAL","28000","no pg_hba.conf entry for host ""[local]"", user ""root"", database ""root"", SSL off",,,,,,,0,,"auth.c",369,"Traceback 0: a12ca6: /usr/local/greenplum-db-3.3.6.6/bin/postgres errstart+0x3e6
Traceback 1: 748915: /usr/local/greenplum-db-3.3.6.6/bin/postgres ClientAuthentication+0x4c5
Traceback 2: 84a4c0: /usr/local/greenplum-db-3.3.6.6/bin/postgres ClosePostmasterPorts+0x5610
Traceback 3: 84b789: /usr/local/greenplum-db-3.3.6.6/bin/postgres PostmasterMain+0x959
Traceback 4: 76bb84: /usr/local/greenplum-db-3.3.6.6/bin/postgres main+0x474
Traceback 5: 4dae6c: /usr/local/greenplum-db-3.3.6.6/bin/postgres _start+0x6c
"

Doug Little

Sr. Data Warehouse Architect | Enterprise Data Management | Orbitz Worldwide
500 W. Madison, Suite 1000 Chicago IL 60661| Office 312.260.2588 | Fax 312.894.5164 | Cell 847-997-5741
Douglas(dot)Little(at)orbitz(dot)com<mailto:Douglas(dot)Little(at)orbitz(dot)com>
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