MapD Core Services and Utilities

Assuming $MAPD_PATH is the directory where MapD Core is installed, make sure that $MAPD_PATH/bin is in PATH:



You can use the commands mapd_server and mapd_web_server for testing and debugging your MapD Core instance. When you start your production server, MapD recommends that you use the systemctl command. See Starting and Stopping MapD Core Services.


mapd_server $MAPD_DATA [--cpu|--gpu]
                       [--config </path/to/mapd.conf>]
                       [--http-port <port number>]
                       [--ldap-uri <string>]
                       [--ldap-dn <string>
                       [--num-gpus <number>]
                       [{-p|--port} <port number>]
                       [--start-gpu <number>]

This command starts the MapD Core Server process. $MAPD_DATA must match that in the initdb command when it was run. The options are:

  • [--cpu|--gpu]: Execute queries on CPU-only or on both GPU and CPU. The default is --gpu. If Xorg and NVIDIA CUDA are not installed, your MapD server automatically executes queries only on the CPU.
  • [--config]: Path to mapd.conf.
  • [--data]: Path to the MapD data directory.
  • [--db-convert]: Only required when converting existing databases from version 2.0.4 to 2.1.0. Path to the source directory.
  • [{-p|--port} <port number>]: Specify the port for MapD Core Server’s binary-over-TCP protocol. The default is port 9091.
  • [{--http-port} <port number>]: Specify the port for MapD Core Server’s JSON-over-HTTP protocol. The default is port 9090.
  • [--ldap-uri <string>]: LDAP URI for authentication, for example ldap://
  • [--ldap-dn <string]: LDAP DN Distinguished Name, defaults to uid=%s,cn=users,cn=accounts,dc=mapd,dc=com. Note: the single %s in this string will be replaced by the username at authentication time.
  • [--flush-log]: Flush log files to disk. Useful for tail -F on log files.
  • [--rendering]: Enables server-based rendering. Defaults to TRUE.
  • [--num-gpus <number>]: Number of GPUs to use, defaults to number detected on hardware.
  • [--start-gpu <number>]: When not using all detected GPUs, start using GPUs at this number, defaults to zero.
  • [--version|-v]: Prints version number.
  • [--help|-h]: Print this help text.


mapd_web_server [{--port} <port number>]
                [{--proxy-backend} <bool>]
                [{--backend-url} <backend URL>]
                [{--frontend} <path/to/frontend>]
                [{--enable-https} <bool>]
                [{--cert} <cert.pem>]
                [{--key} <key.pem>]
                [{--tmpdir} </path/to/tmp>]
                [{--timeout} <1h0m0s>]

This command starts the MapD Core Web Server. This server provides access to the MapD Immerse visualization frontend and allows MapD Immerse to communicate with MapD Core Server. HTTPS certificates and keys may be generated via the provided generate_cert utility, or provided by your Certificate Authority. The options are:

  • [{--port} <port number>]: Specify the port the web server listens on. The default is port 9092.
  • [{--proxy-backend} <bool>]: Specify whether to act as a proxy to the backend. The default is true.
  • [{--backend-url} <backend URL>]: Specify the URL to the backend HTTP server. The default is http://localhost:9090.
  • [{--frontend} <path/to/frontend>]: Specify the path to the MapD Immerse directory. The default is frontend.
  • [{--enable-https} <bool>]: Enable HTTPS for serving MapD Immerse. The default is false.
  • [{--cert} <cert.pem>]: Path to the HTTPS certificate file. The default is cert.pem.
  • [{--key} <key.pem>]: Path to the HTTPS key file. The default is key.pem.
  • [{--tmpdir} </path/to/tmp>]: Path to custom temporary directory. The default is /tmp/.
  • [{--timeout} <1h0m0s>]: Maximum HTTP request duration. The default is 1h0m0s.

The temporary directory is used as a staging location for file uploads. It is sometimes desirable to place this directory on the same file system as the MapD Core data directory. If not specified on the command line, mapd_web_server also respects the standard TMPDIR environment variable as well as a specific MAPD_TMPDIR environment variable, the latter of which takes precedence. Defaults to the system default /tmp/ if neither the command line argument nor at least one of the environment variables are specified.

The --timeout option controls the maximum duration of individual HTTP requests. This is used to manage resource exhaustion caused by improperly closed connections. One side effect of this option is that it limits the execution time of queries made over the Thrift HTTP transport. This timeout duration therefore must be increased if queries are expected to take longer than the default duration of one hour, e.g. if you will be performing a COPY FROM on a large file when using mapdql with the HTTP transport.



The very first step before using MapD Core is to initialize the data directory via initdb:

initdb [-f] $MAPD_DATA

This creates three subdirectories:

  • mapd_catalogs: stores MapD Core’s catalogs
  • mapd_data: stores MapD Core’s data
  • mapd_log: contains all MapD Core’s log files. MapD Core uses glog for logging.

The -f flag forces initdb to overwrite existing data and catalogs in the specified directory.


generate_cert [{-ca} <bool>]
              [{-duration} <duration>]
              [{-ecdsa-curve} <string>]
              [{-host} <host1,host2>]
              [{-rsa-bits} <int>]
              [{-start-date} <string>]

This command generates certificates and private keys for an HTTPS server. The options are:

  • [{-ca} <bool>]: Whether this certificate should be its own Certificate Authority. The default is false.
  • [{-duration} <duration>]: Duration that certificate is valid for. The default is 8760h0m0s.
  • [{-ecdsa-curve} <string>]: ECDSA curve to use to generate a key. Valid values are P224, P256, P384, P521.
  • [{-host} <string>]: Comma-separated hostnames and IPs to generate a certificate for.
  • [{-rsa-bits} <int>]: Size of RSA key to generate. Ignored if –ecdsa-curve is set. The default is 2048.
  • [{-start-date} <string>]: Start date formatted as Jan 1 15:04:05 2011