running in single user mode

[Senthil_Kumar]

I need to develop a client-server application
running on a cluster which will use cluster
interconnect for all its communcation. The
requirement here is to run the server daemon
in single-user mode. I know that in single-
user mode, only essential kernel services are
available. So my question here is - Is it
OK/fine to run my server daemon in single-
user mode?
What are the issues to be considered for
this scenario ?

[Ivan Ferreira]

If this will be a daemon that will accept network connections, you should run in multi-user mode with networking. You can disable the startup of unneeded services in /etc/rc3.d. If you don't want that users can logon to the system, create a /etc/nologin file.

Are you sure that the requisite is to run in single user, or allow a single user to use the daemon?

[Vladimir Fabecic]

There is another idea. You can customeize run level 2(rc2.d). In runlevel 2 you can add startup scripts that you need and desable startup scripts that you do not need. In the same time, "clasic" single user mode will stay original and also will runlevel 3.
So instead "init s" will use "init 2".
This should NOT be done in cluster envirement.

[Hein van den Heuvel]

>>> The requirement here is to run the server daemon in single-user mode.


At first observation that seems a nonsense requirement.

Please explain WHY this is believed to be a requirement.
Perhaps a reader here can address 'the real problem' in a better way than requiring single-user mode.

fwiw,
Hein.