We are installing mongo DB 4.0 on RHEL and facing the below issue when trying to change the default data and log directory in config file.

Aug 03 16:18:28 ralrfdlmgdbpd01 mongod[3219]: 2021-08-03T16:18:28.220-0400 F CONTROL [main] Failed global initialization: FileNotOpen: Failed probe for “/u01/mongodata/log/mongod.log”: Permission denied

Config File

# mongod.conf

# for documentation of all options, see:
#   http://docs.mongodb.org/manual/reference/configuration-options/

# where to write logging data.
systemLog:
  destination: file
  logAppend: true
  path: /u01/mongodata/log/mongod.log

# Where and how to store data.
storage:
  dbPath: /u01/mongodata/lib
  journal:
    enabled: true
#  engine:
#  mmapv1:
#  wiredTiger:

# how the process runs
processManagement:
#  fork: true  # fork and run in background
  pidFilePath: /u01/mongodata/mongod.pid  # location of pidfile
  timeZoneInfo: /usr/share/zoneinfo

# network interfaces
net:
  port: 27017
  bindIp: 127.0.0.1  # Enter 0.0.0.0,:: to bind to all IPv4 and IPv6 addresses or, alternatively, use the net.bindIpAll setting.


#security:

#operationProfiling:

#replication:

#sharding:

## Enterprise-Only Options

#auditLog:

yes, we have granted privileges.

[sysadmin@XXXXXXXX mongodata]$ ls -ltr
total 0
drwxr-xr-x. 2 mongod mongod 6 Aug 3 16:23 lib
drwxr-xr-x. 2 mongod mongod 31 Aug 4 12:20 log
[sysadmin@XXXXXXXX mongodata]$

DB is starting when we run the command.

mongod --dbpath /u01/mongodata/lib --logpath /u01/mongodata/log/mongod.log

we are hitting issue only when starting using service.
service mongod start

It is working when I change the log and data location to /var file system.

I am using root to start the service, not SYSADMIN.

[root@ralrfdlmgdbpd01 lib]# ls -ltr /u01/mongodata
total 0
drwxr-xr-x. 2 mongod mongod 6 Aug 3 16:23 lib
drwxr-xr-x. 2 mongod mongod 31 Aug 4 12:20 log

drwxr-xr-x. 3 mongod mongod 23 Aug 3 16:23 u01
[root@ralrfdlmgdbpd01 /]#

[root@ralrfdlmgdbpd01 u01]# ls -ltr
total 0
drwxr-xr-x. 4 mongod mongod 28 Aug 3 16:23 mongodata

[root@ralrfdlmgdbpd01 mongodata]# ls -ltr
total 0
drwxr-xr-x. 2 mongod mongod 6 Aug 3 16:23 lib
drwxr-xr-x. 2 mongod mongod 31 Aug 4 12:20 log

Hi Steeve,

Sorry for the confusion…

we have been trying with 2 different file systems . /u01 and /data.

right now it is configured with /data.

Here is the config file and service file.

[Unit]
Description=MongoDB Database Server
Documentation=https://docs.mongodb.org/manual
After=network.target

[Service]
User=mongod
Group=mongod
Environment="OPTIONS=-f /etc/mongod.conf"
EnvironmentFile=-/etc/sysconfig/mongod
ExecStart=/usr/bin/mongod $OPTIONS
ExecStartPre=/usr/bin/mkdir -p /var/run/mongodb
ExecStartPre=/usr/bin/chown mongod:mongod /var/run/mongodb
ExecStartPre=/usr/bin/chmod 0755 /var/run/mongodb
PermissionsStartOnly=true
PIDFile=/var/run/mongodb/mongod.pid
Type=forking
# file size
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# locked memory
LimitMEMLOCK=infinity
# total threads (user+kernel)
TasksMax=infinity
TasksAccounting=false
# Recommended limits for for mongod as specified in
# http://docs.mongodb.org/manual/reference/ulimit/#recommended-settings

Config File

# mongod.conf

# for documentation of all options, see:
#   http://docs.mongodb.org/manual/reference/configuration-options/

# where to write logging data.
systemLog:
  destination: file
  logAppend: true
  path: /var/lib/mongo/mongod.log

# Where and how to store data.
storage:
  dbPath: /data/mongodb/lib
  journal:
    enabled: true
#  engine:
#  mmapv1:
#  wiredTiger:

# how the process runs
processManagement:
#  fork: true  # fork and run in background
  pidFilePath: /var/lib/mongo/mongod.pid  # location of pidfile
  timeZoneInfo: /usr/share/zoneinfo

# network interfaces
net:
  port: XXXXX
  bindIp: 127.0.0.1  # Enter 0.0.0.0,:: to bind to all IPv4 and IPv6 addresses or, alternatively, use the net.bindIpAll setting.


#security:

#operationProfiling:

#replication:

#sharding:

## Enterprise-Only Options

#auditLog:

#snmp:

[root@ralrfdlmgdbpd01 system]# cd /data
[root@ralrfdlmgdbpd01 data]# ls -ltr
total 0
drwxr-xr-x. 4 mongod mongod 28 Aug 3 16:28 mongodb
[root@ralrfdlmgdbpd01 data]# cd mongodb
[root@ralrfdlmgdbpd01 mongodb]# ls -ltr
total 0
drwxrwxrwx. 2 mongod mongod 6 Aug 3 16:28 lib
drwxr-xr-x. 2 mongod mongod 24 Aug 3 16:34 log
[root@ralrfdlmgdbpd01 mongodb]# cd lib
[root@ralrfdlmgdbpd01 lib]# ls -ltr
total 0