The cockroach gen
command can generate command-line interface (CLI) utilities (man
pages and a bash
autocompletion script), example SQL data suitable to populate test databases, and an HAProxy configuration file for load balancing a running cluster.
Subcommands
Subcommand | Usage |
---|---|
man |
Generate man pages for CockroachDB. |
autocomplete |
Generate bash or zsh autocompletion script for CockroachDB.Default: bash |
example-data |
Generate example SQL datasets. You can also use the cockroach workload command to generate these sample datasets in a persistent cluster and the cockroach demo <dataset> command to generate these datasets in a temporary, in-memory cluster. |
haproxy |
Generate an HAProxy config file for a running CockroachDB cluster. The node addresses included in the config are those advertised by the nodes. Make sure hostnames are resolvable and IP addresses are routable from HAProxy. Decommissioned nodes are excluded from the config file. |
Synopsis
Generate man pages:
$ cockroach gen man
Generate bash autocompletion script:
$ cockroach gen autocomplete
Generate example SQL data:
$ cockroach gen example-data intro | cockroach sql
$ cockroach gen example-data startrek | cockroach sql
Generate an HAProxy config file for a running cluster:
$ cockroach gen haproxy
View help:
$ cockroach gen --help
$ cockroach gen man --help
$ cockroach gen autocomplete --help
$ cockroach gen example-data --help
$ cockroach gen haproxy --help
Flags
The gen
subcommands supports the following general-use, logging, and client connection flags.
General
man
Flag | Description |
---|---|
--path |
The path where man pages will be generated. Default: man/man1 under the current directory |
autocomplete
Flag | Description |
---|---|
--out |
The path where the autocomplete file will be generated. Default: cockroach.bash in the current directory |
example-data
No flags are supported. See the Generate Example Data example for guidance.
haproxy
Flag | Description |
---|---|
--host |
The server host and port number to connect to. This can be the address of any node in the cluster. Env Variable: COCKROACH_HOST Default: localhost:26257 |
--port -p |
The server port to connect to. Note: The port number can also be specified via --host . Env Variable: COCKROACH_PORT Default: 26257 |
--insecure |
Use an insecure connection. Env Variable: COCKROACH_INSECURE Default: false |
--certs-dir |
The path to the certificate directory containing the CA and client certificates and client key. Env Variable: COCKROACH_CERTS_DIR Default: ${HOME}/.cockroach-certs/ |
--url |
A connection URL to use instead of the other arguments. Env Variable: COCKROACH_URL Default: no URL |
--out |
The path where the haproxy.cfg file will be generated. If an haproxy.cfg file already exists in the directory, it will be overwritten.Default: haproxy.cfg in the current directory |
--locality |
If nodes were started with locality details, you can use the --locality flag here to filter the nodes included in the HAProxy config file, specifying the explicit locality tier(s) or a regular expression to match against. This is useful in cases where you want specific instances of HAProxy to route to specific nodes. See the Generate an HAProxy configuration file example for more details. |
Logging
By default, this command logs messages to stderr
. This includes events with WARNING
severity and higher.
If you need to troubleshoot this command's behavior, you can customize its logging behavior.
Client Connection
haproxy
Flag | Description |
---|---|
--cluster-name |
The cluster name to use to verify the cluster's identity. If the cluster has a cluster name, you must include this flag. For more information, see cockroach start . |
--disable-cluster-name-verification |
Disables the cluster name check for this command. This flag must be paired with --cluster-name . For more information, see cockroach start . |
Examples
Generate man
pages
Generate man pages:
$ cockroach gen man
Move the man pages to the man directory:
$ sudo mv man/man1/* /usr/share/man/man1
Access man pages:
$ man cockroach
Generate a bash
autocompletion script
Generate bash autocompletion script:
$ cockroach gen autocomplete
Add the script to your .bashrc
and .bash_profle
:
$ printf "\n\n#cockroach bash autocomplete\nsource '<path to>cockroach.bash'" >> ~/.bashrc
$ printf "\n\n#cockroach bash autocomplete\nsource '<path to>cockroach.bash'" >> ~/.bash_profile
You can now use tab
to autocomplete cockroach
commands.
Generate example data
You can also use the cockroach workload
command to generate these sample datasets in a persistent cluster and the cockroach demo <dataset>
command to generate these datasets in a temporary, in-memory cluster.
To test out CockroachDB, you can generate an example startrek
database, which contains 2 tables, episodes
and quotes
.
First, start up a demo cluster:
$ cockroach demo
Then, pipe the output from cockroach gen
to the URL to the demo cluster:
$ cockroach gen example-data startrek | cockroach sql --url='postgres://demo:demo11762@127.0.0.1:26257?sslmode=require'
CREATE DATABASE
SET
DROP TABLE
DROP TABLE
CREATE TABLE
INSERT 1
...
CREATE TABLE
INSERT 1
...
Open a SQL shell to view it:
$ cockroach sql --url='postgres://demo:demo11762@127.0.0.1:26257?sslmode=require'
> SHOW TABLES FROM startrek;
schema_name | table_name | type | estimated_row_count
--------------+------------+-------+----------------------
public | episodes | table | 79
public | quotes | table | 200
(2 rows)
You can also generate an example intro
database, which contains 1 table, mytable
, with a hidden message:
$ cockroach gen example-data intro | cockroach sql --url='postgres://demo:demo11762@127.0.0.1:26257?sslmode=require'
CREATE DATABASE
SET
DROP TABLE
CREATE TABLE
INSERT 1
INSERT 1
INSERT 1
INSERT 1
...
# Launch the built-in SQL client to view it:
$ cockroach sql --url='postgres://demo:demo11762@127.0.0.1:26257?sslmode=require'
> SHOW TABLES FROM intro;
schema_name | table_name | type | estimated_row_count
--------------+------------+-------+----------------------
public | mytable | table | 42
(1 row)
> SELECT * FROM intro.mytable WHERE (l % 2) = 0;
l | v
-----+-------------------------------------------------------
0 | !__aaawwmqmqmwwwaas,,_ .__aaawwwmqmqmwwaaa,,
2 | !"VT?!"""^~~^"""??T$Wmqaa,_auqmWBT?!"""^~~^^""??YV^
4 | ! "?##mW##?"-
6 | ! C O N G R A T S _am#Z??A#ma, Y
8 | ! _ummY" "9#ma, A
10 | ! vm#Z( )Xmms Y
12 | ! .j####mmm#####mm#m##6.
14 | ! W O W ! jmm###mm######m#mmm##6
16 | ! ]#me*Xm#m#mm##m#m##SX##c
18 | ! dm#||+*$##m#mm#m#Svvn##m
20 | ! :mmE=|+||S##m##m#1nvnnX##; A
22 | ! :m#h+|+++=Xmm#m#1nvnnvdmm; M
24 | ! Y $#m>+|+|||##m#1nvnnnnmm# A
26 | ! O ]##z+|+|+|3#mEnnnnvnd##f Z
28 | ! U D 4##c|+|+|]m#kvnvnno##P E
30 | ! I 4#ma+|++]mmhvnnvq##P` !
32 | ! D I ?$#q%+|dmmmvnnm##!
34 | ! T -4##wu#mm#pw##7'
36 | ! -?$##m####Y'
38 | ! !! "Y##Y"-
40 | !
(21 rows)
Generate an HAProxy config file
HAProxy is one of the most popular open-source TCP load balancers, and CockroachDB includes a built-in command for generating a configuration file that is preset to work with your running cluster.
To generate an HAProxy config file for an entire secure cluster, run the cockroach gen haproxy
command, specifying the location of certificate directory and the address of any instance running a CockroachDB node:
$ cockroach gen haproxy \
--certs-dir=<path to certs directory> \
--host=<address of any node in the cluster>
To limit the HAProxy config file to nodes matching specific "localities", use the --localities
flag, specifying the explicit locality tier(s) or a regular expression to match against:
$ cockroach gen haproxy \
--certs-dir=<path to certs directory> \
--host=<address of any node in the cluster>
--locality=region=us.*
To generate an HAProxy config file for an entire insecure cluster, run the cockroach gen haproxy
command, specifying the address of any instance running a CockroachDB node:
$ cockroach gen haproxy \
--insecure \
--host=<address of any node in the cluster>
To limit the HAProxy config file to nodes matching specific "localities", use the --localities
flag, specifying the explicit locality tier(s) or a regular expression to match against:
$ cockroach gen haproxy \
--insecure \
--host=<address of any node in the cluster>
--locality=region=us.*
By default, the generated configuration file is called haproxy.cfg
and looks as follows, with the server
addresses pre-populated correctly:
global
maxconn 4096
defaults
mode tcp
# Timeout values should be configured for your specific use.
# See: https://cbonte.github.io/haproxy-dconv/1.8/configuration.html#4-timeout%20connect
timeout connect 10s
timeout client 1m
timeout server 1m
# TCP keep-alive on client side. Server already enables them.
option clitcpka
listen psql
bind :26257
mode tcp
balance roundrobin
option httpchk GET /health?ready=1
server cockroach1 <node1 address>:26257 check port 8080
server cockroach2 <node2 address>:26257 check port 8080
server cockroach3 <node3 address>:26257 check port 8080
The file is preset with the minimal configurations needed to work with your running cluster:
Field | Description |
---|---|
timeout connect timeout client timeout server |
Timeout values that should be suitable for most deployments. |
bind |
The port that HAProxy listens on. This is the port clients will connect to and thus needs to be allowed by your network configuration. This tutorial assumes HAProxy is running on a separate machine from CockroachDB nodes. If you run HAProxy on the same machine as a node (not recommended), you'll need to change this port, as 26257 is likely already being used by the CockroachDB node. |
balance |
The balancing algorithm. This is set to roundrobin to ensure that connections get rotated amongst nodes (connection 1 on node 1, connection 2 on node 2, etc.). Check the HAProxy Configuration Manual for details about this and other balancing algorithms. |
option httpchk |
The HTTP endpoint that HAProxy uses to check node health. /health?ready=1 ensures that HAProxy doesn't direct traffic to nodes that are live but not ready to receive requests. |
server |
For each included node, this field specifies the address the node advertises to other nodes in the cluster, i.e., the addressed pass in the --advertise-addr flag on node startup. Make sure hostnames are resolvable and IP addresses are routable from HAProxy. |
For full details on these and other configuration settings, see the HAProxy Configuration Manual.
See also
- Other Cockroach Commands
- Deploy CockroachDB On-Premises (using HAProxy for load balancing)