perfSONAR User Q&A and Other Discussion

[Brian Candler <>]

I've just done some fresh installs with the 4.1.2 toolkit ISO.

I notice that pscheduler uses a non-system uid and gid of 1000:

pscheduler:x:1000:1000:pScheduler:/home/pscheduler:/bin/bash

Then, some other accounts are using system uids but non-system gids:

esmond:x:993:1001:Esmond User:/tmp:/sbin/nologin
perfsonar:x:991:1002:perfSONAR User:/tmp:/sbin/nologin

Plus, the pssudo group is a non-system gid:

pscheduler:x:1000:
esmond:x:1001:
perfsonar:x:1002:
pssudo:x:1003:

This means that my "regular" CentOS user (created during the ISO 
install) gets uid 1001 and gid 1004, which is messy.

In theory, system users should have uids and gids between 201 and 999.  
There is a flag to useradd for this:

       -r, --system
           Create a system account.

           System users will be created with no aging information in
           /etc/shadow, and their numeric identifiers are chosen in the
           SYS_UID_MIN-SYS_UID_MAX range, defined in /etc/login.defs, 
instead
           of UID_MIN-UID_MAX (and their GID counterparts for the 
creation of
           groups).

           Note that useradd will not create a home directory for such an
           user, regardless of the default setting in /etc/login.defs
           (CREATE_HOME). You have to specify the -m options if you want a
           home directory for a system account to be created.

And also to groupadd:

       -r, --system
           Create a system group.

           The numeric identifiers of new system groups are chosen in the
           SYS_GID_MIN-SYS_GID_MAX range, defined in login.defs, instead of
           GID_MIN-GID_MAX.

Is this behaviour because of the installer, or the way the rpm packages 
are built (e.g. is it post-install scripts creating the uids/gids)?  
Either way, would it be worth tweaking them to get more normal behaviour?

Regards,

Brian.

P.S. The regular user I created in the installer had the "administrator" 
box checked, and it ended up in group wheel, but not pssudo.