Comdb2 has been running in production on x86 Linux, PowerPC AIX, and SPARC Solaris systems. This guide is written with Linux in mind. Admin commands for other OSes will be different, but database commands will remain the same.

Installing from source

You can pull the latest source from GitHub.

git clone
cd comdb2

Our development policy is to tag each release. Major releases are branched. Building from the latest commit in the latest branch is a good bet. Master is for bleeding edge development.


You’ll need to install a few dependencies first. It’s not a big list. Exact names will depend on your distribution type and version. Dependencies for some major distributions:

Distro Dependencies
Ubuntu 16.04, 16.10 sudo apt-get install -y build-essential bison flex libprotobuf-c-dev libreadline-dev libsqlite3-dev libssl-dev libunwind-dev libz1 libz-dev make gawk protobuf-c-compiler uuid-dev liblz4-tool liblz4-dev libprotobuf-c1 libsqlite3-0 libuuid1 libz1 tzdata ncurses-dev tcl bc
CentOS 7 sudo yum install -y gcc gcc-c++ protobuf-c libunwind libunwind-devel protobuf-c-devel byacc flex openssl openssl-devel openssl-libs readline-devel sqlite sqlite-devel libuuid libuuid-devel zlib-devel zlib lz4-devel gawk tcl epel-release lz4 which


Just run make.


sudo USER='username' make install

To make testing out Comdb2 easier, make install will use the value of $USER to set ownership of log/configuration directories. For a personal/development install sudo USER=$(whoami) make install is a good option. For database deployments, create a dedicated user.

Comdb2 installs by default rely on a small program called pmux to deal out port numbers to databases. Port assignments are dynamic. This is very useful if you run large numbers of databases and don’t want to manage port assignment yourself. You’ll need to start this program on system startup. For systemd-based systems, we provide a pmux.service file. If you’re going to be running databases as the current user, you’re all set. To use a dedicated user, change the User= line in tools/pmux/pmux.service To use it:

sudo cp tools/pmux/pmux.service /etc/systemd/system
sudo systemctl daemon-reload
sudo systemctl enable pmux
sudo systemctl start pmux

Installing from a package

Packages can be built from source with make deb-current on Debian-derived systems, or make rpm-current on Redhat-derived systems.

Installing a package creates a comdb2 user and group and installs pmux and cdb2sockpool as systemd-managed services. Log/data directories are set up with read/write permissions for the comdb2 user. Databases should be created and run as comdb2. As a convenience, installing from a package also starts an instance of supervisord that can be used to manage running databases. A simple script called comdb2admin is installed to make it easier to start/create databases through supervisord.

Installation directories

Installing (from source or a package) creates a directory structure like this:

├── bin
│   ├── cdb2_dump
│   ├── cdb2_printlog
│   ├── cdb2_pgdump
│   ├── cdb2sql
│   ├── cdb2_stat
│   ├── cdb2_verify
│   ├── comdb2
│   ├── comdb2ar
│   ├── comdb2dumpcsc
│   ├── copycomdb2
│   └── pmux
│   └── comdb2admin
├── etc
│   └── cdb2
│       └── config
│           ├── comdb2.d
│           └── comdb2.lrl
├── include
│   └── cdb2api.h
├── lib
│   ├── libcdb2api.a
│   ├──
└── var
    ├── cdb2
    └── logs
        └── cdb2

A quick overview:

Directory Notes
bin/ Programs. comdb2 is the main Comdb2 binary. Other programs are helpers that allow copying/backing up/examining/operating databases.
etc/cdb2/config/comdb2.lrl Global database tunables, applies to all databases
etc/cdb2/config/comdb2.d Global database config files, settings in all *.lrl files in this directory apply to all databases
include/ and lib/ headers and libraries
var/cdb2/ Default location for databases. Every database gets a subdirectory at create time.
var/logs/cdb2/ Default location for database informational log files