mongodb cant start centos 7 - mongodb

Question

I installed mongodb on Centos 7 and all works fine.
But if I reboot the system, mongodb can't start anymore. If I uninstall and install again, works fine. But after reboot, cant start anymore.
When I try systemctl status mongod.service shows:
mongod.service - High-performance, schema-free document-oriented database
Loaded: loaded (/usr/lib/systemd/system/mongod.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Dom 2016-11-27 09:49:36 BRT; 12min ago
Docs: https://docs.mongodb.org/manual
Process: 1471 ExecStart=/usr/bin/mongod $OPTIONS run (code=exited, status=1/FAILURE)
Main PID: 1471 (code=exited, status=1/FAILURE)
Nov 27 09:49:19 localhost.localdomain systemd[1]: Started High-performance, schema-free document-oriented database.
Nov 27 09:49:19 localhost.localdomain systemd[1]: Starting High-performance, schema-free document-oriented database...
Nov 27 09:49:36 localhost.localdomain mongod[1471]: about to fork child process, waiting until server is ready for connections.
Nov 27 09:49:36 localhost.localdomain mongod[1471]: forked process: 2828
Nov 27 09:49:36 localhost.localdomain mongod[1471]: ERROR: child process failed, exited with error number 1
Nov 27 09:49:36 localhost.localdomain systemd[1]: mongod.service: main process exited, code=exited, status=1/FAILURE
Nov 27 09:49:36 localhost.localdomain systemd[1]: Unit mongod.service entered failed state.
Nov 27 09:49:36 localhost.localdomain systemd[1]: mongod.service failed.
I already tried:
*chcon -R -t mongod_var_lib_t /var/lib/mongo
*SElinux=disable
*chmod 7777 /var/lib/mongo
and nothing.
I remember when this error appeared before I format my pc, I needed to put permission on systemd with a simple command. But I cant find anymore.

Answer 1

here is the official bug report
https://jira.mongodb.org/browse/SERVER-27241
in
/usr/lib/systemd/system/mongod.service
update the systemd service with the following, till they fix it officially
[Service]
User=mongod
Group=mongod
Environment="OPTIONS=--quiet -f /etc/mongod.conf"
PermissionsStartOnly=true
ExecStartPre=/usr/bin/mkdir /var/run/mongodb
ExecStartPre=/usr/bin/chown -R mongod:mongod /var/run/mongodb
ExecStart=/usr/bin/mongod $OPTIONS run
PIDFile=/var/run/mongodb/mongod.pid

Answer 2

I remove and reinstall Mongodb 3.4
The server started with: sudo systemctl start mongod.service, and started ok.
Here's the /var/log/mongodb/mongod.log
2016-11-27T13:23:03.600-0300 I CONTROL [main] ***** SERVER RESTARTED
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] MongoDB
starting : pid=8247 port=27017 dbpath=/var/lib/mongo 64-bit
host=localhost.localdomain
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] db version
v3.4.0-rc5
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] git version:
7df8fe1099135d137516f1670d2a0091ace63ca0
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] OpenSSL
version: OpenSSL 1.0.1e-fips 11 Feb 2013
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] allocator:
tcmalloc
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] modules: none
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] build
environment:
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] distmod:
rhel70
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] distarch:
x86_64
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten]
target_arch: x86_64
2016-11-27T13:23:03.612-0300 I CONTROL [initandlisten] options: {
command: [ "run" ], config: "/etc/mongod.conf", net: { bindIp:
"127.0.0.1", port: 27017 }, processManagement: { fork: true,
pidFilePath: "/var/run/mongodb/mongod.pid" }, storage: { dbPath:
"/var/lib/mongo", journal: { enabled: true } }, systemLog: {
destination: "file", logAppend: true, path:
"/var/log/mongodb/mongod.log", quiet: true } }
2016-11-27T13:23:03.971-0300 I - [initandlisten] Detected data
files in /var/lib/mongo created by the 'wiredTiger' storage engine,
so setting the active storage engine to 'wiredTiger'.
2016-11-27T13:23:03.971-0300 I STORAGE [initandlisten]
wiredtiger_open config:
create,cache_size=1329M,session_max=20000,eviction=(threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000),checkpoint=(wait=60,log_size=2GB),statistics_log=(wait=0),
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten]
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] ** WARNING:
Access control is not enabled for the database.
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] **
Read and write access to data and configuration is unrestricted.
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten]
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten]
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] ** WARNING:
/sys/kernel/mm/transparent_hugepage/enabled is 'always'.
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] ** We
suggest setting it to 'never'
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten]
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] ** WARNING:
/sys/kernel/mm/transparent_hugepage/defrag is 'always'.
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten] ** We
suggest setting it to 'never'
2016-11-27T13:23:05.036-0300 I CONTROL [initandlisten]
2016-11-27T13:23:05.061-0300 I FTDC [initandlisten] Initializing
full-time diagnostic data capture with directory '/var/lib/monenter
code herego/diagnostic.data'
2016-11-27T13:23:05.061-0300 I NETWORK [thread1] waiting for
connections on port 27017
When i reboot the sytem, Mongodb wont start again.
Heres the log:
logAppend: true path: /var/log/mongodb/mongod.log
*# Where and how to store data.
2016-11-27T13:30:27.927-0300 I CONTROL [main] ***** SERVER RESTARTED
2016-11-27T13:30:28.279-0300 I CONTROL [main] ERROR: Cannot write pid
file to /var/run/mongodb/mongod.pid: No such file or directory
Here is my /etc/mongod.conf
storage:
dbPath: /var/lib/mongo
journal:
enabled: true
*# engine:
*# mmapv1:
*# wiredTiger:
*# how the process runs
processManagement: fork: true # fork and run in background
pidFilePath: /var/run/mongodb/mongod.pid # location of pidfile
*# network interfaces net: port: 27017 bindIp: 127.0.0.1 # Listen to local interface only, comment to listen on all interfaces.
*# security:
*# operationProfiling:
*# replication:
*# sharding:
*## Enterprise-Only Options
*# auditLog:
*# snmp:

Answer 3

I also ran into that on CentOS 7 and mongodb 3.4. Here's how I solved it:
Edit /etc/mongod.conf file and change fork to false and pidFilePath to the same as dbPath (which for me is /var/lib/mongo):
/etc/mongod.conf:
storage:
dbPath: /var/lib/mongo
processManagement:
fork: false # fork and run in background
pidFilePath: /var/lib/mongo/mongod.pid # location of pidfile
net:
port: 27017
bindIp: 0.0.0.0
Don't forget to set firewall rules and reload:
firewall-cmd --zone=public --permanent --add-port=27017/tcp; firewall-cmd --reload
Follow log file and restart:
tail -f /var/log/mongodb/mongod.log &
systemctl restart mongod; systemctl status mongod
You should see in last line of log file:
NETWORK [thread1] waiting for connections on port 27017
It worked for me, I rebooted the system and I could connect to mongo straight away.