HP3000/HP 3000 FAQ

Last Updated: Thursday, February 01, 2007 02:38 PM

What exactly counts toward the 'user license' limit on my HP3000?

3.10. What exactly counts toward the 'user license' limit on my HP3000?

Details of what does and does not count toward the user limit are listed below:

Counts toward user limit
-------------------------
1. A user logon from a terminal or PC is counted when using one of
   the following connections:

   - DTC direct connect
   - DTC modem connect
   - LAN (PC only)

  - X.25
   - PBX
   - Statistical Multiplexer
   - NS virtual terminal (Pt-to-Pt, LAN, X.25)
   - PAD

2. An application which calls HPFOPEN or FOPEN on a terminal other
   than its own will increment the user limit for each additional
   terminal opened.

Does not count directly toward the user limit
----------------------------------------------
1. The physical console will always be available and will NOT
   count toward the user limit.

2. Sessions have not been used to keep track of the user limit
   since some applications can initiate multiple sessions for a
   single user.

3. Jobs do not typically count toward the user limit unless the
   job is running an application which is opening a terminal.

4. Processes do not directly relate to the user limit because it is
   possible for a single process to HPFOPEN multiple terminals. As
   well as, a single user can run an application that creates
   multiple processes.

5. Remote applications which do not establish a virtual terminal
   do not count toward the user limit. A common example of this
   is Remote File Access. A user performing a dscopy with the
   logon option does not count.

In summary, the user count tracks individual users interacting
with the system through an open terminal or PC connection.


-----------part #2 (clarifying article on NULL VT) ---------------

BY:  James Hofmeister - Network Expert Center Atlanta
     Eero Laurila     - CSY Networking lab, NS services, VT.

This is a quick article to clear up a misconception with the functionality of "NULLVT" in the NS3000/iX product.

NS3000/iX supports a facility called "NULLVT", which is the ability to open a terminal device on a system for logon, but it specifically excludes the ability to do any terminal I/O with the system.

An example of one implementation demonstrating this functionality is the HP Resource Sharing product which supports multiple inbound connections from one PC to the HP3000 - while counting the PC as one user. This product allows the PC user to share discs and printers attached to the HP3000 - i.e. using it as a file and print server. The thing to note here is that there is no terminal I/O involved with the client.

On the technical side, allocating an ldev for terminal I/O is needed to satisfy MPE's requirements for logon. The way that VT's terminal I/O works is that a device that has been allocated for input/output (stdin/stdlist) will have a logical device manager (vt_ldm) attached to it.

The vt_ldm forwards I/O requests from MPE/iX's High-Level I/O (HLIO) subsystem to the client and vice versa through a vtserver process who owns the TCP-connection on the host. Also, the vt_ldm is created by the server process that allocates the device (in this case vtserver.net.sys).

Depending on which way the vt_ldm is created, the initialization info sent to the ldm tells whether the device is to be used for real I/O or "null" I/O. When created as a "null" terminal, the vt_ldm's state is set to indicate that there is no vtserver process to take care of forwarding data between the host and client and thus all the terminal I/O received from HLIO (High-Level I/O) is to be flushed.

Other NS services for example NFT(dscopy) and RFA(remote file access) can and will also use the "nullvt" functionality. If the user specifies a logon string in DSLINE [node];LOGON= parm, this results in a programmatic logon executed on the remote node through a null VT-terminal. Note that also in this case the device is allocated strictly for the logon purposes and there is no interactive communication with the remote host nor is there a server to take care of it. Using other NS services in this fashion saves resources on the host by eliminating the need for creating an extra server process (vtserver) to handle the terminal I/O that will not occur on NFT-only or RFA-only connection.

The misconception of the functionality in the "NULLVT" facility is the result of an article generated, as a Question / Answer response to a Customer User Group.

The text of the article should read:

Q: Does a single PC running multiple sessions on the server count as one or multiple users on the HP 3000?

A: Each session logged on to the HP 3000 doing terminal I/O is counted towards user licence. All VT-connections will create a vtserver process that allocates a device for "real" terminal I/O.

Example: Some MS Window clients offer multiple VT connections from a single PC to the HP 3000 Server. Each VT logon is a unique session and is counted as a session against the user license.