Licensing¶

Who needs a license for kdb+?¶

Everyone. All use of kdb+ is governed by a license. Without one, kdb+ signals an error 'k4.lic and aborts.

64-bit installations require a license key file: k4.lic, or kc.lic for kdb+ On Demand.

If both are found, the kc.lic file is used.

Obtain a license key file¶

A license file can be a commercial license or an on-demand person license (for non-commercial use).

On-Demand License¶

It requires a kc.lic license key file and an always-on internet connection to operate.

Licensing server¶

If kdb+ with an on-demand license cannot contact the KX license server it will abort with a timestamped message.

'2018.03.28T11:20:03.831 couldn't connect to license daemon -- exiting

If an HTTP proxy is required, the environment variables http_proxy or HTTP_PROXY define the URL of the HTTP proxy to use. Since 4.1t 2022.11.01,4.0 2022.10.26,4.0ce 2022.09.16 the on-demand system honours the NO_PROXY/no_proxy environment variables, with the lowercase version taking precedence.

Commercial License¶

Use of commercial kdb+ is covered by your license agreement with KX.

Your copy of kdb+ will need access to a valid license key file.

If you wish to begin using kdb+ commercially, please contact sales@kx.com.

Install the license key file¶

Save a copy of the license key file (k4.lic or kc.lic) in the QHOME folder. (See installation instructions for your operating system.) Restart your kdb+ session and note the change in the banner.

tom@mb13:~/q$ q
KDB+ 3.6 2018.07.30 Copyright (C) 1993-2018 Kx Systems
m64/ 2()core 8192MB tom mb13.local 192.168.1.44 EXPIRE 2019.05.15 tom@kx.com #400
q)til 6
0 1 2 3 4 5
q)

Note the license number (#400 in the example) and quote it in any correspondence about the license.

If you are sharing use of a commercial license, you will probably want to set the environment variable QLIC to the path of the license key file, as below.

License errors¶

A list of possible errors can be found here.

Keeping the license key file elsewhere¶

The default location for the license key file is the QHOME folder. You do not have to keep the license key file there. You can use the environment variable QLIC to specify a different filepath.

Folder not file

Like QHOME, QLIC points to a folder, not a file. For example,

QLIC='/Users/simon/q'

Core restrictions¶

If the license is for fewer cores than the total number on the machine, the number of cores available to kdb+ must be restricted with OS programs, or kdb+ will signal 'cores and abort.

KDB+ 3.6 2018.07.30 Copyright (C) 1993-2018 Kx Systems
m64/ 4(3)core 16384MB simon simon-macos.local 127.0.0.1   simon@kx.com #40000

'cores

As long as you use taskset or numa correctly, the binary will not abort itself.

You can see the number of cores entitled to a q process:

by looking at the banner, e.g. …m64/ 4(3)core… – the 4 here is the number of cores reported by the OS, and the 3 is the number of cores licensed
with .z.c – not the physical cores of the system, but rather the number the process is allowed to use
the first element of .z.l

The number of licensed cores is always 16 for the on-demand license.

On the road

The license key file binds the interpreter to your computer’s hostname. For example, for a Mac named mymbp the hostname might be mymbp.local. When traveling you may find a network has changed the hostname, for example to mymbp.lan or mymbp.fritz.box. kdb+ then signals a host error on launch.

Linux and macOS users can restore their hostnames from the command shell, e.g.

scutil --set HostName "mymbp.local"

License questions¶

Designated Contacts should send license questions to licadmin@kx.com.

Emergency failover licenses¶

In case of an emergency, such as a hardware or infrastructure failure that renders your license key file unusable, the Designated Contact can email failover@kx.com to request a temporary failover license to allow use of a different machine or IP address.