postgres backup (pg_basebackup) is failed.

here are the details: 

postgres version : 11.2

[postgres@pglinux1:/oraworkspace/pg_scripts ] $ psql -V

psql (PostgreSQL) 11.2

pg_basebackup version: 

[postgres@pglinux1:/oraworkspace/pg_scripts ] $ pg_basebackup -V

pg_basebackup (PostgreSQL) 11.2

os version 

[postgres@pglinux1:/oraworkspace/pg_scripts ] $ cat /etc/redhat-release

Red Hat Enterprise Linux Server release 7.3 (Maipo)

backup command 

[postgres@pglinux1:/oraworkspace/pg_scripts ] $

[postgres@pglinux1:/oraworkspace/pg_scripts ] $ pg_basebackup -h localhost -p 5400 -D /oraworkspace/pgbackup/5400backup --waldir=/oraworkspace/pgbackup/bkpwal_log --checkpoint=fast --wal-method=stream -v

pg_basebackup: initiating base backup, waiting for checkpoint to complete

pg_basebackup: checkpoint completed

pg_basebackup: write-ahead log start point: 9/5B000028 on timeline 1

pg_basebackup: directory "/oradbaudit/pg_data_tbsp" exists but is not empty

pg_basebackup: removing contents of data directory "/oraworkspace/pgbackup/5400backup"

pg_basebackup: removing contents of WAL directory "/oraworkspace/pgbackup/bkpwal_log"

[postgres@pglinux1:/oraworkspace/pg_scripts ] $ timed out waiting for input: auto-logout

postgres alert log 

2019-05-03 17:16:00.204 GMT [6646] [unknown] [unknown] [unknown] localhost(53866) 00000 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT LOG:  connection received: host=localhost port=53866

2019-05-03 17:16:00.206 GMT [6646] [unknown] postgres [unknown] localhost(53866) 00000 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT LOG:  replication connection authorized: user=postgres

2019-05-03 17:16:00.245 GMT [6474]     00000 5ccc7743.194a 0 2019-05-03 17:15:47 GMT LOG:  checkpoint starting: immediate force wait

2019-05-03 17:16:00.260 GMT [6474]     00000 5ccc7743.194a 0 2019-05-03 17:15:47 GMT LOG:  checkpoint complete: wrote 0 buffers (0.0%); 0 WAL file(s) added, 1 removed, 0 recycled; write=0.003 s, sync=0.000 s, total=0.014 s; sync files=0, longest=0.000 s, average=0.000 s; distance=16384 kB, estimate=16384 kB

2019-05-03 17:16:00.348 GMT [6646] pg_basebackup postgres [unknown] localhost(53866) 08006 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT LOG:  could not send data to client: Connection reset by peer

2019-05-03 17:16:00.348 GMT [6646] pg_basebackup postgres [unknown] localhost(53866) XX000 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT ERROR:  base backup could not send data, aborting backup

2019-05-03 17:16:00.349 GMT [6646] pg_basebackup postgres [unknown] localhost(53866) 08006 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT LOG:  could not send data to client: Broken pipe

2019-05-03 17:16:00.349 GMT [6646] pg_basebackup postgres [unknown] localhost(53866) 08006 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT FATAL:  connection to client lost

2019-05-03 17:16:00.349 GMT [6646] pg_basebackup postgres [unknown] localhost(53866) 00000 5ccc7750.19f6 0 2019-05-03 17:16:00 GMT LOG:  disconnection: session time: 0:00:00.145 user=postgres database= host=localhost port=53866