Could not able to start mongod as a service

[Alisher]

Dear Champs,

I want to start mongod as a service, but I could not able to do that I am facing errors.

I installed mongo community server 4.2 rpm packages on redhat linux 7 I wanted to use my own mongod.conf file rather than the default once. (find the attached mongod.conf file for reference)

mongod.conf.txt

As to start mongod as a service which means (sudo service mongod start) I edited the systemd/system/mongod.service file (find the attached mongod.service file)

mongod.service.txt

After above all when I try to start mongod I am getting below error.

Can any one please help me out with this.

Thanks and Best Regards,

Alisher.

mongod.conf.txt (488 Bytes)

mongod.service.txt (255 Bytes)

[Evgeniy_Patlan]

hi @Alisher

As I can see from the provided screenshot mongod service couldn’t read config file due to incorrect permissions

“Error reading config file: Permission denied” So please check permissions.

Also after the modifications of systemd unit-file it is recommended to run sudo systemctl daemon-reload before starting service

[Alisher]

I gave 755 permissions to config file and also after the modifications on systemd unit-file I executed “sudo systemctl daemon-reload” but no luck.

[vinicius.grippa]

Alisher,

Please provide the log and the new error message after applying Evgenity suggestions.

[Evgeniy_Patlan]

@Alisher

You need to modify your systemd unit-file in the following way:

===========================================

[Unit]

Description=MongoDB Database Server

Documentation=https://docs.mongodb.org/manual

After=network.target

[Service]

User=mongod

Group=mongod

Environment=“OPTIONS=-f /home/mongod/config/mongod.conf”

ExecStart=/usr/bin/mongod $OPTIONS

[Install]

WantedBy=multi-user.target

============================================

Also in mongod.conf please remove

fork: true

Additionally

permissions on your /home/mongod directory and it’s subdirectories should be

owner - mongod

group - mongod

and permissions 755

With such setup I was able to correctly start mongod

[Alisher]

Hi @Evgeniy and vinicius.grippa

I deployed as per the above comments again I am facing same issue.

Below is updated mongod.service file , after updating the mongodb.service file I even did ‘sudo systemctl daemon-reload’

Below screen shot of updated mongod.conf file

Below screen shot permissions for mongod.conf file

Below screen shot for directories with permissions

If I try to check log file , it didn’t even get created.

Thanks and Regards,

Alisher.

[Evgeniy_Patlan]

@Alisher

What are the permissions for /home/mongod?

[Alisher]

@Evgeniy_Patlan

Below are the permissions for /home and /mongod

drwxr-xr-x. 3 root root 20 Nov 17 05:04 home

drwxr-xr-x. 8 mongod mongod 180 Nov 17 06:29 mongod

even though I am getting below error when I start.

[mongod@mongst01 home]$ sudo service mongod start

Redirecting to /bin/systemctl start mongod.service

[mongod@mongst01 home]$ sudo service mongod status

Redirecting to /bin/systemctl status mongod.service

● mongod.service - MongoDB Database Server

Loaded: loaded (/usr/lib/systemd/system/mongod.service; enabled; vendor preset: disabled)

Active: failed (Result: exit-code) since Tue 2020-11-17 07:45:38 UTC; 7s ago

 Docs: <a href="https://docs.mongodb.org/manual">https://docs.mongodb.org/manual</a>

Process: 2642 ExecStart=/usr/bin/mongod $OPTIONS (code=exited, status=2)

Main PID: 2642 (code=exited, status=2)

Nov 17 07:45:38 mongst01 systemd[1]: Started MongoDB Database Server.

Nov 17 07:45:38 mongst01 mongod[2642]: Error reading config file: Permission denied

Nov 17 07:45:38 mongst01 mongod[2642]: try ‘/usr/bin/mongod --help’ for more information

Nov 17 07:45:38 mongst01 systemd[1]: mongod.service: main process exited, code=exited, status=2/INVALIDARGUMENT

Nov 17 07:45:38 mongst01 systemd[1]: Unit mongod.service entered failed state.

Nov 17 07:45:38 mongst01 systemd[1]: mongod.service failed.

[mongod@mongst01 home]$

[Evgeniy_Patlan]

@Alisher

the main issue is:

Error reading config file: Permission denied

So you should carefully check check permissions, also maybe you can find some additional information in /var/log/messages

[Akira_Kurogane]

Evegniy - I believe that fork should be true in the config file.

Although we used stdout log capture into journald with PBM, and PBM doesn’t have a fork option (yet), it would be pretty uncommon to run mongod that way. Whether MongoDB Community edition or Percona Server for MongoDB.

[Bronco]

Please try to run it manually on the command line, with mongod user

/usr/bin/mongod -f /home/mongod/config/mongod.conf

This will tell you that you have a strange parameter on the your conf file.

You don’t have a log file because mongod never started. (or mongod can not write to /home/mongod/logs)

Make sure that mongod user can write on the directories /home/mongod/logs and /home/mongod/data.

A simple touch should do the trick with your mongod user

touch /home/mongod/logs/PleaseDeleteMe

touch /home/mongod/logs/data

(Your service file shouldn’t be a concern at this point.)

Make sure:

• that you don’t have a sock file (normally on /tmp) owned by root. The same for pid file and for log file (log file doesn’t seem to exist)

-That all locations that mongod needs to write are writable by mongod

If the problem is still happening:

I would replace with a normal conf file and adapt it slowly to your requirements. (yaml notation is very picky).

Try it until you get it started. on every attempt try a “less /home/mongod/logs/mongod.log”

If it starts on the command line you can normally kill it by a simple kill <pid_of_the_mongod_process>.

From this point try to start using the service

[Bronco]

BTW

I tried with your original conf file and it works. (I have changed everything from /home to /tmp)

/usr/local/bin/mongod -f ./Downloads/mongod.conf.txt

2020-11-27T17:28:15.098+0000 I CONTROL [main] Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols ‘none’

about to fork child process, waiting until server is ready for connections.

forked process: 28416

child process started successfully, parent exiting

Directory permissions should be the issue. (or existing sock, pid, log file owned by root)