mongostat

--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.

--uri=<connectionString>

New in version 3.4.6.

Specify a resolvable URI connection string (enclose in quotes) to connect to the MongoDB deployment.

--uri="mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]"

For information on the components of the connection string, see the Connection String URI Format documentation.

NOTE:

IMPORTANT:

--host=<hostname><:port>, -h=<hostname><:port>

Default: localhost:27017

Specifies a resolvable hostname for the mongod to which to connect. By default, the 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>,<...>

Changed in version 3.0.0: 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>]).

NOTE:

--port=<port>

Default: 27017

Specifies the TCP port on which the MongoDB instance listens for client connections.

NOTE:

--ipv6

Removed in version 3.0.

Enables IPv6 support and allows mongostat to connect to the MongoDB instance using an IPv6 network. Prior to MongoDB 3.0, you had to specify --ipv6 to use IPv6. In MongoDB 3.0 and later, IPv6 is always enabled.

--ssl

New in version 2.6.

Enables connection to a mongod or mongos that has TLS/SSL support enabled.

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslCAFile=<filename>

New in version 2.6.

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.

Starting in version 3.4, if --tlsCAFile/net.tls.CAFile (or their aliases --sslCAFile/net.ssl.CAFile) is not specified and you are not using x.509 authentication, the system-wide CA certificate store will be used when connecting to an TLS/SSL-enabled server.

To use x.509 authentication, --tlsCAFile or net.tls.CAFile must be specified unless using --tlsCertificateSelector or --net.tls.certificateSelector. Or if using the ssl aliases, --sslCAFile or net.ssl.CAFile must be specified unless using --sslCertificateSelector or net.ssl.certificateSelector.

WARNING:

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslPEMKeyFile=<filename>

New in version 2.6.

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 has CAFile enabled without allowConnectionsWithoutCertificates.

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslPEMKeyPassword=<value>

New in version 2.6.

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, the mongostat 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 ssl-certificate-password.

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslCRLFile=<filename>

New in version 2.6.

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, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslAllowInvalidCertificates

New in version 2.6.

Bypasses the validation checks for server certificates and allows the use of invalid certificates. When using the allowInvalidCertificates setting, MongoDB logs as a warning the use of the invalid certificate.

Starting in MongoDB 4.0, if you specify --sslAllowInvalidCertificates or net.ssl.allowInvalidCertificates: true (or in MongoDB 4.2, the alias --tlsAllowInvalidateCertificates or net.tls.allowInvalidCertificates: true) when using x.509 authentication, an invalid certificate is only sufficient to establish a TLS/SSL connection but is insufficient for authentication.

WARNING:

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-clients .

--sslAllowInvalidHostnames

New in version 3.0.

Disables the validation of the hostnames in TLS/SSL certificates. Allows mongostat to connect to MongoDB instances even if the hostname in their certificates do not match the specified hostname.

For more information about TLS/SSL and MongoDB, see /tutorial/configure-ssl and /tutorial/configure-ssl-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.

NOTE:

--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.

Changed in version 3.0.2: 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="" .

NOTE:

--authenticationDatabase=<dbname>

Specifies the authentication database where the specified --username has been created. See user-authentication-database.

NOTE:

--authenticationDatabase is required for mongod and mongos instances that use authentication.

--authenticationMechanism=<name>

Default: SCRAM-SHA-1

Specifies the authentication mechanism the mongostat instance uses to authenticate to the mongod or mongos.

Changed in version 4.0: MongoDB removes support for the deprecated MongoDB Challenge-Response (MONGODB-CR) authentication mechanism.

MongoDB adds support for SCRAM mechanism using the SHA-256 hash function (SCRAM-SHA-256).

Value	Description
SCRAM-SHA-1	RFC 5802 standard Salted Challenge Response Authentication Mechanism using the SHA-1 hash function.
SCRAM-SHA-256	RFC 7677 standard Salted Challenge Response Authentication Mechanism using the SHA-256 hash function. Requires featureCompatibilityVersion set to 4.0. New in version 4.0.
MONGODB-X509	MongoDB TLS/SSL certificate authentication.
GSSAPI (Kerberos)	External authentication using Kerberos. This mechanism is available only in MongoDB Enterprise.
PLAIN (LDAP SASL)	External authentication using LDAP. You can also use PLAIN for authenticating in-database users. PLAIN transmits passwords in plain text. This mechanism is available only in MongoDB Enterprise.

NOTE:

--gssapiServiceName=<string>

New in version 2.6.

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>

New in version 2.6.

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

New in version 3.4.

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>

New in version 3.4.

When specified, mongostat includes only the specified fields in the mongostat output.

Use dot notation to specify serverStatus fields, as in metrics.document.inserted.

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:

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>

New in version 3.4.

When specified, mongostat includes the specified serverStatus fields after the default mongostat output.

Use dot notation to specify serverStatus fields, as in metrics.document.inserted.

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 a mongostat 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.

Changed in version 2.6: When running with --discover, mongostat now respects --rowcount.

--http

Configures mongostat to collect data using the HTTP interface rather than a raw database connection.

Changed in version 3.6: MongoDB 3.6 removes the deprecated HTTP interface and REST API to MongoDB.

--all

Configures mongostat to return all optional fields.

--json

New in version 3.0.0.

Returns output for mongostat in JSON format.

--interactive

New in version 3.4.

Display mongostat output in an interactive non-scrolling interface rather than the default scrolling output.

--interactive is not available with the --json option.

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, that mongostat 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.

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. On secondary systems, mongostat presents two values separated by a pipe character (e.g. |), in the form of local|replicated commands.

flushes

Changed in version 3.0.

For the storage-wiredtiger, flushes refers to the number of WiredTiger checkpoints triggered between each polling interval.

dirty

New in version 3.0.

Only for storage-wiredtiger. The percentage of the WiredTiger cache with dirty bytes, calculated by wiredTiger.cache.tracked dirty bytes in the cache / wiredTiger.cache.maximum bytes configured.

used

New in version 3.0.

Only for storage-wiredtiger. The percentage of the WiredTiger cache that is in use, calculated by wiredTiger.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

Changed in version 3.0: Only appears when mongostat runs against pre-3.0 versions of MongoDB instances.

The percent of time in a global write lock.

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.

Value	Replication Type
M	master
SEC	secondary
REC	recovering
UNK	unknown
RTR	mongos process ("router")
ARB	arbiter

• /reference/command/serverStatus
• /reference/command/replSetGetStatus
• /reference/command/dbStats
• /reference/command/collStats