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Connection Options
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This section explains the MongoDB connection and authentication options supported by the driver. You can pass the connection options as parameters of the connection URI to specify the behavior of the client.
Name | Accepted Values | Default Value | Description |
|---|---|---|---|
appname | string | null | Specifies the app name the driver passes to the server in the client
metadata as part of the connection handshake. The server prints the
appname to the MongoDB logs upon establishing the connection.
It is also recorded in the slow query logs and profile collections. |
authMechanism | string | null | Specifies the authentication mechanism method to use for connection to the
server. If you do not specify a value, the driver uses the default mechanism,
either SCRAM-SHA-1 or SCRAM-SHA-256 depending on the server version. See
authentication mechanism for available
authentication mechanisms. |
authMechanismProperties | comma separated key:value pairs, e.g. "opt1:val1,opt2:val2" | null | Specifies additional options provided for authentication, such as
enabling hostname canonicalization for GSSAPI. |
authSource | string | null | Specifies the database that connections should authenticate against. |
compressors | comma separated list of strings, e.g. "snappy,zlib" | null | Specifies the allowed compression types for wire protocol messages
sent to or received from the server. See Network Compression
for more information. |
connectTimeoutMS | non-negative integer | 30000 | Specifies the amount of time, in milliseconds, to wait to establish a single TCP
socket connection to the server before raising an error. Specifying
0 disables the connection timeout. |
directConnection | boolean | false | Specifies whether to force dispatch all operations to the host
specified in the connection URI. |
heartbeatFrequencyMS | integer greater than or equal to 500 | null | Specifies the interval, in milliseconds, between regular server monitoring checks. |
journal | boolean | null | Specifies the default write concern "j" field for the client. See
write concern for more information. |
loadBalanced | boolean | null | Specifies whether the driver is connecting to a load balancer. |
localThresholdMS | non-negative integer | 15 | Specifies the size of the latency window, in milliseconds, on round trip time for
selecting between suitable servers. Specifying 0 means no wait,
meaning the fastest available server. |
maxIdleTimeMS | non-negative integer | 0 | Specifies the amount of time, in milliseconds, a connection can be idle before it's closed.
Specifying 0 means no minimum. |
maxPoolSize | non-negative integer | 100 | Specifies the maximum number of clients or connections the driver
can create in its connection pool. This count includes connections
in use. |
maxConnecting | non-negative integer | 2 | Specifies the maximum number of connections a driver's connection
pool may be establishing concurrently. |
maxStalenessSeconds | -1, or an integer greater than or equal 90 | null | Specifies the maximum replication lag, in wall clock time, that
a secondary can experience and still be eligible for server selection.
Specifying -1 means no maximum. |
minPoolSize | non-negative integer | 0 | Specifies the number of connections the driver should create and
maintain in the connection pool even when no operations are occurring.
This count includes connections in use. |
proxyHost | string | null | Specifies the IPv4/IPv6 address or domain name of a SOCKS5 proxy
server used for connecting to MongoDB services. |
proxyPort | non-negative integer | null | Specifies the port of the SOCKS5 proxy server specified in proxyHost. |
proxyUsername | string | null | Specifies the username for username/password authentication to the SOCKS5
proxy server specified in proxyHost. |
proxyPassword | string | null | Specifies the password for username/password authentication to the SOCKS5
proxy server specified in proxyHost. |
readConcernLevel | string | null | Specifies the default read concern for the client. See read concern for more information. |
readPreference | string | "primary" | Specifies the default read preference for the client (excluding tags). See read preference for more information. |
readPreferenceTags | comma-separated key:value pairs (e.g. "dc:ny,rack:1" and "dc:ny)
can be specified multiple times, each instance of this key is a
separate tag set | null | Specifies the default read preference tags for the client. This option is valid only if the read preference mode is not primary. The driver uses the order of the tags in the URI as the order for the read preference. |
replicaSet | string | null | Specifies the name of the replica set to connect to. |
retryReads | boolean | true | Enables retryable reads. |
retryWrites | boolean | true | Enables retryable writes. |
serverSelectionTimeoutMS | non-negative integer | 30000 | Specifies the timeout, in milliseconds, to block for server selection
before raising an error. |
serverSelectionTryOnce | boolean | true | Specifies to scan the topology only once after a server selection
failure instead of repeatedly until the server selection times out. |
socketTimeoutMS | non-negative integer | 0 | Specifies the amount of time, in milliseconds, spent attempting to send or receive on a
socket before timing out. Specifying 0 means no timeout. |
srvMaxHosts | non-negative integer | 0 | Specifies the maximum number of SRV results to randomly select when initially
populating the seedlist or, during SRV polling, adding new hosts to the
topology. |
srvServiceName | a valid SRV service name according to RFC 6335 | "mongodb" | Specifies the service name to use for SRV lookup in initial DNS seedlist discovery. |
ssl | boolean | false | The ssl is an alias for the tls option. |
timeoutMS | non-negative integer | unset (feature is not enabled by default) | Specifies the timeout, in milliseconds, for the full execution of an operation. |
tls | boolean | false | Specifies whether TLS is required for connections to the server.
Using a srvServiceName of "mongodb+srv", or specifying other
tls prefixed options will default tls to true. |
tlsAllowInvalidCertificates | boolean | false | Specifies whether the driver should error when the server’s
TLS certificate is invalid. |
tlsAllowInvalidHostnames | boolean | false | Specifies whether the driver should error when there is a mismatch
between the server’s hostname and the hostname specified by the
TLS certificate. |
tlsCAFile | string | null | Specifies the path to a file with either a single or bundle of certificate
authorities to trust when making a TLS connection. |
tlsCertificateKeyFile | string | null | Specifies the path to the client certificate file or the client
private key file. If you need both, you must concatenate the files. |
tlsCertificateKeyFilePassword | string | null | Specifies the password to decrypt the client private key to be used
for TLS connections. |
tlsInsecure | boolean | false | Specifies to relax TLS constraints as much as possible, such as
allowing invalid certificates or hostname mismatches. |
w | non-negative integer or string | null | Specifies the default write concern "w" field for the client. |
waitQueueTimeoutMS | non-negative integer | 0 | Specifies the amount of time, in milliseconds, spent attempting to check out a connection
from a server's connection pool before timing out. |
wTimeoutMS | non-negative integer | null | Specifies the default write concern "wtimeout" field for the client. |
zlibCompressionLevel | integer between -1 and 9 (inclusive) | -1 | Specifies the level of compression when using zlib to compress wire
protocol messages. -1 signifies the default level, 0 signifies
no compression, 1 signifies the fastest speed, and 9 signifies
the best compression. See Network Compression for more information. |