incomplete startup packet messages in logs

Hi Team,

I know this is has been answered a lot on the internet wrt ignoring,
but i am unable to figure out why I get these messages in logs
"incomplete startup packet"

I have a server running postgresql 10.5 on ubuntu16.04

i do not have any active external connections other than streaming
postgres replication.


postgres  7757     1  0 12:20 ?        00:00:00
/usr/lib/postgresql/10/bin/postgres -D /var/lib/postgresql/10/main -c
config_file=/etc/postgresql/10/main/postgresql.conf

postgres  7759  7757  0 12:20 ?        00:00:00 postgres: 10/main:
checkpointer process

postgres  7760  7757  0 12:20 ?        00:00:00 postgres: 10/main:
writer process

postgres  7761  7757  0 12:20 ?        00:00:00 postgres: 10/main: wal
writer process

postgres  7762  7757  0 12:20 ?        00:00:00 postgres: 10/main:
autovacuum launcher process

postgres  7763  7757  0 12:20 ?        00:00:00 postgres: 10/main:
archiver process

postgres  7764  7757  0 12:20 ?        00:00:00 postgres: 10/main:
stats collector process

postgres  7765  7757  0 12:20 ?        00:00:00 postgres: 10/main:
bgworker: logical replication launcher

postgres  7779  7757  0 12:20 ?        00:00:00 postgres: 10/main: wal
sender process replicator x.x.x.x(47792) streaming 3/FA0001B0

postgres  7780  7757  0 12:20 ?        00:00:00 postgres: 10/main: wal
sender process replicator x.x.x.x(50526) streaming 3/FA0001B0

postgres  7786  7757  0 12:21 ?        00:00:00 postgres: 10/main: wal
sender process barman_streaming x.x.x.x(43566) streaming 3/FA0001B0



also,

postgres=# select backend_type, query from pg_stat_activity;

    backend_type     |                       query

---------------------+---------------------------------------------------

 autovacuum launcher |

 background worker   |

 walsender           |

 walsender           |

 walsender           |

 client backend      | select backend_type, query from pg_stat_activity;

 background writer   |

 checkpointer        |

 walwriter           |



but i still see


tail -1000 /var/log/postgresql/postgresql-10-main.log| grep
'incomplete startup packet'

2018-11-01 13:04:18 UTC LOG:  incomplete startup packet

2018-11-01 13:08:18 UTC LOG:  incomplete startup packet

2018-11-01 13:12:18 UTC LOG:  incomplete startup packet


Note: exactly at 4 min interval.

i do not know C, but i tried to understand something from

https://github.com/postgres/postgres/blob/197e4af9d5da180190a0f2be851b095dba57d9cd/src/backend/postmaster/postmaster.c#L1891

without any active connections, i would rule any driver issue out.

i do not have ssl enabled, but not using it. I tried disabling it too.

postgres=# show ssl;

 ssl

-----

 off

(1 row)



I do not know, why those log messages are then showing up.

not errors in

ens160    Link encap:Ethernet  HWaddr 00:50:56:a4:53:b6

          inet addr:x.x.x.x  Bcast:x.x.x.x Mask:x.x.x.x

          inet6 addr: xxxxx/64 Scope:Link

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:45403371 errors:0 dropped:0 overruns:0 frame:0

          TX packets:8834699 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:6417380742 (6.4 GB)  TX bytes:56209193635 (56.2 GB)


lo        Link encap:Local Loopback

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:65536  Metric:1

          RX packets:28985185 errors:0 dropped:0 overruns:0 frame:0

          TX packets:28985185 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1

          RX bytes:7078785550 (7.0 GB)  TX bytes:7078785550 (7.0 GB)







Regards,
Vijay