mongostat (original) (raw)
This documentation is for version 100.10.0
of mongostat
.
mongostat
is a command-line tool that provides a quick overview of the status of a currently running mongod ormongos instance. Use mongostat
to help identify system bottlenecks.
mongostat
is functionally similar to the UNIX/Linux file system utility vmstat
, but provides data regarding mongod and mongosinstances.
Run mongostat
from the system command line, not themongo shell.
mongostat
syntax:
mongostat <options> <connection-string> <polling interval in seconds>
--help
Returns information on the options and use of mongostat
.
--verbose, -v
Increases the amount of internal reporting returned on standard output or in log files. Increase the verbosity with the -v
form by including the option multiple times, (e.g. -vvvvv
.)
--version
Returns the mongostat
release number.
--config=<filename>
New in version 100.3.0.
Specifies the full path to a YAML configuration file containing sensitive values for the following options to mongostat
:
This is the recommended way to specify a password to mongostat
, aside from specifying it through a password prompt.
The configuration file takes the following form:
password: <password>
uri: mongodb://mongodb0.example.com:27017
sslPEMKeyPassword: <password>
Specifying a password to the password:
field and providing a connection string in the uri:
field which contains a conflicting password will result in an error.
Be sure to secure this file with appropriate filesystem permissions.
Note
If you specify a configuration file with --config and also use the --password, --uri or--sslPEMKeyPassword option to mongostat
, each command line option overrides its corresponding option in the configuration file.
--uri=<connectionString>
Specifies the resolvable URI connection string of the MongoDB deployment, enclosed in quotes:
--uri="mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]"
Starting with version 100.0
of mongostat
, the connection string may alternatively be provided as a positional parameter, without using the --uri option:
mongostat mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]
As a positional parameter, the connection string may be specified at any point on the command line, as long as it begins with eithermongodb://
or mongodb+srv://
. For example:
mongostat --username joe --password secret1 mongodb://mongodb0.example.com:27017 --ssl
Only one connection string can be provided. Attempting to include more than one, whether using the --uri option or as a positional argument, will result in an error.
For information on the components of the connection string, see the Connection String URI Format documentation.
Note
Some components in the connection string may alternatively be specified using their own explicit command-line options, such as --username and --password. Providing a connection string while also using an explicit option and specifying conflicting information will result in an error.
Note
If using mongostat
on Ubuntu 18.04, you may experience acannot unmarshal DNS
error message when usingSRV connection strings (in the form mongodb+srv://
) with the --uri option. If so, use one of the following options instead:
- the --uri option with a non-SRV connection string (in the form
mongodb://
) - the --host option to specify the host to connect to directly
Warning
On some systems, a password provided in a connection string with the --uri option may be visible to system status programs such as ps
that may be invoked by other users. Consider instead:
- omitting the password in the connection string to receive an interactive password prompt, or
- using the --config option to specify a configuration file containing the password.
--host=<hostname><:port>, -h=<hostname><:port>
Default: localhost:27017
Specifies the resolvable hostname of the MongoDB deployment. By default, mongostat
attempts to connect to a MongoDB instance running on the localhost on port number 27017
.
To connect to a replica set, you can specify the set member or members to report on, as in the following (see also the--discover
flag):
--host=<hostname1><:port>,<hostname2><:port>,<...>
If you use IPv6 and use the <address>:<port>
format, you must enclose the portion of an address and port combination in brackets (e.g. [<address>]
).
Alternatively, you can also specify the hostname directly in theURI connection string. Providing a connection string while also using --host and specifying conflicting information will result in an error.
--port=<port>
Default: 27017
Specifies the TCP port on which the MongoDB instance listens for client connections.
Alternatively, you can also specify the port directly in theURI connection string. Providing a connection string while also using --port and specifying conflicting information will result in an error.
--ssl
Enables connection to a mongod or mongos that has TLS/SSL support enabled.
Alternatively, you can also configure TLS/SSL support directly in theURI connection string. Providing a connection string while also using --ssl and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--sslCAFile=<filename>
Specifies the .pem
file that contains the root certificate chain from the Certificate Authority. Specify the file name of the.pem
file using relative or absolute paths.
Alternatively, you can also specify the .pem
file directly in theURI connection string. Providing a connection string while also using --sslCAFile and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--sslPEMKeyFile=<filename>
Specifies the .pem
file that contains both the TLS/SSL certificate and key. Specify the file name of the .pem
file using relative or absolute paths.
This option is required when using the --ssl option to connect to a mongod or mongos that hasCAFile enabled without allowConnectionsWithoutCertificates.
Alternatively, you can also specify the .pem
file directly in theURI connection string. Providing a connection string while also using --sslPEMKeyFile and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--sslPEMKeyPassword=<value>
Specifies the password to de-crypt the certificate-key file (i.e.--sslPEMKeyFile). Use the--sslPEMKeyPassword option only if the certificate-key file is encrypted. In all cases, themongostat
will redact the password from all logging and reporting output.
If the private key in the PEM file is encrypted and you do not specify the --sslPEMKeyPassword option, the mongostat
will prompt for a passphrase. See TLS/SSL Certificate Passphrase.
Alternatively, you can also specify the password directly in theURI connection string. Providing a connection string while also using --sslPEMKeyPassword and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
Warning
On some systems, a password provided directly using the--sslPEMKeyPassword option may be visible to system status programs such as ps
that may be invoked by other users. Consider using the --config option to specify a configuration file containing the password instead.
--sslCRLFile=<filename>
Specifies the .pem
file that contains the Certificate Revocation List. Specify the file name of the .pem
file using relative or absolute paths.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--sslAllowInvalidCertificates
Bypasses the validation checks for server certificates and allows the use of invalid certificates. When using theallowInvalidCertificates setting, MongoDB logs as a warning the use of the invalid certificate.
Warning
Although available, avoid using the--sslAllowInvalidCertificates
option if possible. If the use of --sslAllowInvalidCertificates
is necessary, only use the option on systems where intrusion is not possible.
Connecting to a mongod ormongos instance without validating server certificates is a potential security risk. If you only need to disable the validation of the hostname in the TLS/SSL certificates, see --sslAllowInvalidHostnames
.
Alternatively, you can also disable certificate validation directly in theURI connection string. Providing a connection string while also using --sslAllowInvalidCertificates and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--sslAllowInvalidHostnames
Disables the validation of the hostnames in TLS/SSL certificates. Allowsmongostat
to connect to MongoDB instances even if the hostname in their certificates do not match the specified hostname.
Alternatively, you can also disable hostname validation directly in theURI connection string. Providing a connection string while also using --sslAllowInvalidHostnames and specifying conflicting information will result in an error.
For more information about TLS/SSL and MongoDB, seeConfigure mongod and mongos for TLS/SSL andTLS/SSL Configuration for Clients.
--username=<username>, -u=<username>
Specifies a username with which to authenticate to a MongoDB database that uses authentication. Use in conjunction with the--password and--authenticationDatabase options.
Alternatively, you can also specify the username directly in theURI connection string. Providing a connection string while also using --username and specifying conflicting information will result in an error.
If connecting to a MongoDB Atlas cluster using the MONGODB-AWS
authentication mechanism, you can specify your AWS access key ID in:
- this field,
- the connection string, or
- the
AWS_ACCESS_KEY_ID
environment variable.
See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.
--password=<password>, -p=<password>
Specifies a password with which to authenticate to a MongoDB database that uses authentication. Use in conjunction with the--username and--authenticationDatabase options.
To prompt the user for the password, pass the --username option without--password or specify an empty string as the --password value, as in --password=""
.
Alternatively, you can also specify the password directly in theURI connection string. Providing a connection string while also using --password and specifying conflicting information will result in an error.
If connecting to a MongoDB Atlas cluster using the MONGODB-AWS
authentication mechanism, you can specify your AWS secret access key in:
- this field,
- the connection string, or
- the
AWS_SECRET_ACCESS_KEY
environment variable.
See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.
Warning
On some systems, a password provided directly using the--password option may be visible to system status programs such as ps
that may be invoked by other users. Consider instead:
- omitting the --password option to receive an interactive password prompt, or
- using the --config option to specify a configuration file containing the password.
--awsSessionToken=<AWS Session Token>
If connecting to a MongoDB Atlas cluster using the MONGODB-AWS
authentication mechanism, and using session tokens in addition to your AWS access key ID and secret access key, you can specify your AWS session token in:
- this field,
- the
AWS_SESSION_TOKEN
authMechanismPropertiesparameter to the connection string, or - the
AWS_SESSION_TOKEN
environment variable.
See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.
Only valid when using the MONGODB-AWS
authentication mechanism.
--authenticationDatabase=<dbname>
Specifies the authentication database where the specified--username has been created. SeeAuthentication Database.
--authenticationDatabase is required for mongodand mongos instances that use Authentication on Self-Managed Deployments.
If using the GSSAPI (Kerberos),PLAIN (LDAP SASL), or MONGODB-AWS
authentication mechanisms, you must set --authenticationDatabase to $external
.
Alternatively, you can also specify the authentication database directly in theURI connection string. Providing a connection string while also using --authenticationDatabase and specifying conflicting information will result in an error.
--authenticationMechanism=<name>
Default: SCRAM-SHA-1
Specifies the authentication mechanism the mongostat
instance uses to authenticate to the mongod or mongos.
Changed in version 100.1.0: Starting in version 100.1.0
, mongostat
adds support for the MONGODB-AWS
authentication mechanism when connecting to aMongoDB Atlas cluster.
Alternatively, you can also specify the authentication mechanism directly in theURI connection string. Providing a connection string while also using --authenticationMechanism and specifying conflicting information will result in an error.
--gssapiServiceName=<string>
Specify the name of the service using GSSAPI/Kerberos. Only required if the service does not use the default name of mongodb
.
This option is available only in MongoDB Enterprise.
--gssapiHostName=<string>
Specify the hostname of a service using GSSAPI/Kerberos. Only required if the hostname of a machine does not match the hostname resolved by DNS.
This option is available only in MongoDB Enterprise.
--humanReadable=<boolean>
Default: true
When true
, mongostat
formats dates and quantity values for easier reading, as in the following sample output:
insert query update delete getmore command dirty used flushes vsize res qrw arw net_in net_out conn time
991 *0 *0 *0 0 2|0 3.4% 4.5% 0 2.90G 297M 0|0 0|0 12.9m 84.2k 2 Oct 6 09:45:37.478
989 *0 *0 *0 0 2|0 3.6% 4.7% 0 2.91G 310M 0|0 0|0 12.9m 84.1k 2 Oct 6 09:45:38.476
988 *0 *0 *0 0 1|0 3.7% 4.8% 0 2.92G 323M 0|0 0|0 12.8m 83.8k 2 Oct 6 09:45:39.481
976 *0 *0 *0 0 2|0 3.9% 5.0% 0 2.94G 335M 0|0 0|0 12.7m 83.7k 2 Oct 6 09:45:40.476
When false
, mongostat
returns the raw data, as in the following sample output:
insert query update delete getmore command dirty used flushes vsize res qrw arw net_in net_out conn time
992 *0 *0 *0 0 2|0 1.3 2.4 0 2941255680 149946368 0|0 0|0 12913607 84271 2 2016-10-06T09:45:25-04:00
989 *0 *0 *0 0 1|0 1.5 2.6 0 2974810112 163577856 0|0 0|0 12873225 84087 2 2016-10-06T09:45:26-04:00
996 *0 *0 *0 0 1|0 1.6 2.8 0 2972712960 177209344 0|0 0|0 12955423 84345 2 2016-10-06T09:45:27-04:00
987 *0 *0 *0 0 1|0 1.8 2.9 0 2989490176 190840832 0|0 0|0 12861852 84008 2 2016-10-06T09:45:28-04:00
-o=<field list>
When output fields are specified with -o, only the specified fields are included in the mongostat
output.
Use dot notation to specifyserverStatus fields, as inmetrics.document.inserted.
A custom field name can include spaces. If you include a space, do not put additional quotes around the field name. To specify a custom name for a field, use <field>=<customName>
, as in:
mongostat -o='host=H,time=T,version=MongoDB Version'
-o supports the following methods to modify the information returned for a given serverStatus field:
.rate()
Use .rate() to view the rate per second at which a serverStatus field is changing from mongostat
call to call.
View Rate of Change for a Field with .rate() illustrates how to usemongostat
with -o and the.rate() method.
.diff()
Use .diff() to view how much a serverStatus field has changed since the previous mongostat
call. The interval between calls is specified by <sleeptime>
.
View Field Changes with .diff() illustrates how to usemongostat
with -o and the.diff() method.
mongostat
supports specifying either -o or -O: you cannot include both options.
See Specify mongostat Output Fields for an example of-o.
-O=<field list>
When specified, mongostat
includes the specifiedserverStatus fields after the defaultmongostat
output.
Use dot notation to specifyserverStatus fields, as inmetrics.document.inserted.
A custom field name can include spaces. If you include a space, do not put additional quotes around the field name. To specify a custom name for a field, use <field>=<customName>
, as in:
mongostat -O=host=H,time=T
mongostat
supports specifying either -O or -o: you cannot include both options.
See Add Fields to mongostat Output for an example of-O.
--noheaders
Disables the output of column or field names.
--rowcount=<number>, -n=<number>
Controls the number of rows to output. Use in conjunction with the sleeptime
argument to control the duration of amongostat
operation.
Unless --rowcount is specified, mongostat
will return an infinite number of rows (e.g. value of 0
.)
--discover
Discovers and reports on statistics from all members of a replica set or sharded cluster. When connected to any member of a replica set, --discover all non-hidden members of the replica set. When connected to a mongos,mongostat
will return data from all shards in the cluster. If a replica set provides a shard in the sharded cluster,mongostat
will report on non-hidden members of that replica set.
The mongostat --host option is not required but potentially useful in this case.
When running with --discover,mongostat
respects--rowcount.
--all
Configures mongostat
to return all optional fields.
--json
Returns output for mongostat
in JSON format.
--interactive
Display mongostat
output in an interactive non-scrolling interface rather than the default scrolling output.
--interactive is not available with the --jsonoption.
See: View Statistics in an Interactive Interface for an example of --interactive.
<sleeptime>
Default: 1
The final mongostat
argument is the length of time, in seconds, thatmongostat
waits in between calls. By default mongostat
returns one call every second.
mongostat
returns values that reflect the operations over a 1 second period. For values of <sleeptime>
greater than 1, mongostat
averages data to reflect average operations per second.
mongostat
returns values that reflect the operations over a 1 second period. When mongostat has a value greater than 1, mongostat
averages the statistics to reflect average operations per second.
mongostat
outputs the following fields:
inserts
The number of objects inserted into the database per second. If followed by an asterisk (e.g. *
), the datum refers to a replicated operation.
query
The number of query operations per second.
update
The number of update operations per second.
delete
The number of delete operations per second.
getmore
The number of get more (i.e. cursor batch) operations per second.
command
The number of commands per second. Onsecondary systems, mongostat
presents two values separated by a pipe character (e.g. |
), in the form oflocal|replicated
commands.
flushes
For the WiredTiger Storage Engine, flushes
refers to the number of WiredTiger checkpoints triggered between each polling interval.
dirty
Only for WiredTiger Storage Engine. The percentage of the WiredTiger cache with dirty bytes, calculated bywiredTiger.cache.tracked dirty bytes in the cache/ wiredTiger.cache.maximum bytes configured.
used
Only for WiredTiger Storage Engine. The percentage of the WiredTiger cache that is in use, calculated bywiredTiger.cache.bytes currently in the cache /wiredTiger.cache.maximum bytes configured.
vsize
The amount of virtual memory in megabytes used by the process at the time of the last mongostat
call.
res
The amount of resident memory in megabytes used by the process at the time of the last mongostat
call.
locked
The percent of time in a global write lock. Only appears whenmongostat
runs against pre-3.0 versions of MongoDB instances.
qr
The length of the queue of clients waiting to read data from the MongoDB instance.
qw
The length of the queue of clients waiting to write data from the MongoDB instance.
ar
The number of active clients performing read operations.
aw
The number of active clients performing write operations.
netIn
The amount of network traffic, in bytes, received by the MongoDB instance.
This includes traffic from mongostat
itself.
netOut
The amount of network traffic, in bytes, sent by the MongoDB instance.
This includes traffic from mongostat
itself.
conn
The total number of open connections.
set
The name, if applicable, of the replica set.
repl
The replication status of the member.
For more information about monitoring MongoDB, seeMonitoring for MongoDB.
For more background on other MongoDB status outputs see:
For an additional utility that provides MongoDB metrics seemongotop.