PostgreSQL-11 Streaming Replication Slave Recovering

Also this is postgresql Log(Debug1 level) . after i restart slave node this
logs accours.
/var/lib/pgsql/11/data/log/postgresql-Fri.log
2019-03-22 12:17:57.869 +03 [31760] LOG: redo starts at 0/C000098
2019-03-22 12:17:57.869 +03 [31760] LOG: consistent recovery state reached
at 0/C0000D0
*2019-03-22 12:17:57.869 +03 [31760] LOG: invalid record length at
0/C0000D0: wanted 24, got 0*
2019-03-22 12:17:57.870 +03 [31757] LOG: database system is ready to
accept read only connections
2019-03-22 12:17:57.877 +03 [31764] LOG: started streaming WAL from
primary at 0/C000000 on timeline 1

Ali Mumcu <alimumcu1077@gmail.com>, 22 Mar 2019 Cum, 12:07 tarihinde şunu
yazdı:

Hello Friends,

I wanna to create Streaming Replication with 2 Node(1 Master, 1 Slave)
After i create streaming replication, streaming is okay , and than when i
add new record on master , than on slave records occurs autamaticly.

but When i look service status on slave server i "see startup recovering
00000001000000000000000A"

[root@slave]# systemctl status postgresql-11
● postgresql-11.service - PostgreSQL 11 database server
Loaded: loaded (/usr/lib/systemd/system/postgresql-11.service;
disabled; vendor preset: disabled)
Active: active (running) since Fri 2019-03-22 11:52:17 +03; 22s ago
Docs: https://www.postgresql.org/docs/11/static/
Process: 29349 ExecStartPre=/usr/pgsql-11/bin/postgresql-11-check-db-dir
${PGDATA} (code=exited, status=0/SUCCESS)
Main PID: 29355 (postmaster)
CGroup: /system.slice/postgresql-11.service
├─29355 /usr/pgsql-11/bin/postmaster -D /var/lib/pgsql/11/data/
├─29357 postgres: logger
*├─29358 postgres: startup recovering
000000010000000000000008*
├─29359 postgres: checkpointer
├─29360 postgres: background writer
├─29361 postgres: stats collector
└─29362 postgres: walreceiver streaming 0/A0000D0

when on master create new wal_file(like *000000010000000000000009)* and
then on slave this is updating on slave like "*startup recovering
000000010000000000000009* "

Is that a problem or not i dont know?

Master And Slave Postgresql.conf file
listen_addresses = '*'
wal_level = replica
synchronous_commit = on
max_wal_senders = 10
wal_keep_segments = 64
hot_standby = on
hot_standby_feedback = on

Slave Recovery.conf file
standby_mode = on
primary_conninfo = 'host=master_ip user=user password=password
application_name=slave'
recovery_target_timeline = 'latest'

Also i trace postgresql process on slave Node . This is results
[root@slave os1077]# strace -p 29358
strace: Process 29358 attached
epoll_wait(4, [], 1, 639) = 0
close(4) = 0
read(7, 0x7ffe72a52007, 1) = -1 EAGAIN (Resource temporarily
unavailable)
epoll_create1(EPOLL_CLOEXEC) = 4
epoll_ctl(4, EPOLL_CTL_ADD, 11, {EPOLLIN|EPOLLERR|EPOLLHUP, {u32=34908528,
u64=34908528}}) = 0
epoll_ctl(4, EPOLL_CTL_ADD, 7, {EPOLLIN|EPOLLERR|EPOLLHUP, {u32=34908552,
u64=34908552}}) = 0
epoll_wait(4, strace: Process 29358 detached
<detached ...>

--
ALİ MUMCU
İSTANBUL ÜNİVERSİTESİ
BİLGİ İŞLEM DAİRE BAŞKANLIĞI
Dahili:11210

On Fri, Mar 22, 2019 at 12:07:27PM +0300, Ali Mumcu wrote:

when on master create new wal_file(like *000000010000000000000009)* and
then on slave this is updating on slave like "*startup recovering
000000010000000000000009* "

Is that a problem or not i dont know?

That's normal. From the point of view of the startup process, which
is the one in charge of replaying WAL data and checking when it is
available from the different sources (local pg_wal, archives with
restore_command or streaming), then this status means "I am recovering
WAL records that are within this WAL segment".
--
Michael