I am aware that we have 5 License Units on Community Edition. But I have issues figuring out how it's working. I have Community Edition
USER>write $system.License.KeyCustomerName()
InterSystems IRIS Community
Freshly started system, only terminal session open, so, only one license units used, and 4 left. As expected
USER>write $system.License.LUConsumed()
1
USER>write $system.License.LUAvailable()
4
Quote from documentation - $SYSTEM.License.[MaxConnections](https://docs.intersystems.com/irislatest/csp/documatic/%25CSP.Documatic.cls?LIBRARY=%25SYS&CLASSNAME=%25SYSTEM.License#MaxConnections)() returns the maximum number of connections a user can make while consuming one license unit. 
USER>write $system.License.MaxConnections()
25
It says 25 connections, let's try using them, and start a few background jobs (Running ^Integrity as a background job this way, was not a good idea though, as it run into endless loop and took 100% of CPU)
USER>zn "%SYS" 

%SYS>for i=1:1 { Job ^Integrity::0 Quit:'$Test  write !,$ZChild } 

21694
21695
21696
21697
So, I got only 4 child processes, well, in sum we have 5 connections only, not 25 as MaxConnections says, check the License Units, stays the same
%SYS>w $system.License.LUConsumed()
1
%SYS>write $system.License.LUAvailable()
4
Looks like I have some space left, but not exactly. So, looks like this user (irisowner in case of docker, it uses system user) does not have any access, anymore
$ docker exec -it iris iris session iris
<LICENSE LIMIT EXCEEDED>
I tried, to login as another user, and wanted to switch off Operation System login ![](/sites/default/files/inline/images/images/image(4297).png) But, it did not work, I keep getting <LICENSE LIMIT EXCEEDED> error So, I stopped one of the background jobs, so, I'll get some place for irisowner. And now I got username prompt. This is not what I would expect at all. Why is that user affect at all.
irisowner@352dab0e513d:/opt/irisapp$ iris session iris 
Node: 352dab0e513d, Instance: IRIS 

Username:
Then I decided to login as another user, for this time as _SYSTEM, and check how many background jobs I can run
%SYS>for i=1:1 { Job ^Integrity::0 Quit:'$Test  write !,$ZChild } 

%SYS>write $username
_SYSTEM
looks like, no space left, at all. we have the first session, 4 jobs with ^Integrity, -1 killed, and one more session already under _SYSTEM, so, only 5 connections again
%SYS>write $system.License.LUAvailable()
4
%SYS>w $system.License.LUConsumed()
1
License Units, keeps, saying the same, that I still have some place   Ok, let's try another way. We have python out of the box. Let's try it
irisowner@352dab0e513d:/opt/irisapp$ /usr/irissys/bin/irispython
Python 3.8.10 (default, Nov 26 2021, 20:14:08)
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import iris
Traceback (most recent call last):
  File "&lt;stdin>", line 1, in &lt;module>
  File "/usr/irissys/lib/python/iris.py", line 14, in &lt;module>
    from pythonint import *
ImportError: IrisStart failed: IRIS_LICENSE (-20)
>>>
Nope, no way. So, I decided to free one connection, and try python again
>>> import iris
Traceback (most recent call last):
  File "&lt;stdin>", line 1, in &lt;module>
  File "/usr/irissys/lib/python/iris.py", line 14, in &lt;module>
    from pythonint import *
ImportError: IrisStart failed: IRIS_ACCESSDENIED (-15)
That was completely unexpected again, so. I was just tried to import library, it was not supposed to fail even if no licenses left. Well, that happens because, default configuration does not permit it at all (%Service_Callin not enabled), kind of weird. Am, I'm doing something wrong? How to get real numbers and usage from $SYSTEM.License, I found nothing close to what I would expect. License Usage keeps saying, that I have some more license units available, but, it is not so. From what I see, that. It does not matter how many License units available, only 5 connections, no matter which user is using it will be available, and there is no way to monitor it.
%SYS>w $system.License.ConnectionCount("_SYSTEM")
0
%SYS>w $system.License.ConnectionCount("irisowner")
0