[Info-vax] OpenVMS STARTUP Whitepaper

[geze...@rlgsc.com]

On Wednesday, December 9, 2020 at 12:06:46 AM UTC-5, Dave Froble wrote:
> On 12/8/2020 7:34 PM, geze... at rlgsc.com wrote: 
> > On Tuesday, December 8, 2020 at 5:45:55 PM UTC-5, Dave Froble wrote: 
> >> On 12/8/2020 11:10 AM, geze... at rlgsc.com wrote: 
> >>> On Monday, December 7, 2020 at 9:49:22 PM UTC-5, Edgar Ulloa wrote: 
> >>>> El jueves, 3 de diciembre de 2020 a las 10:56:44 UTC-5, geze... at rlgsc.com escribió: 
> >>>>> I have posted a whitepaper on OpenVMS STARTUP, discussing the capabilities of STARTUP.COM and its related files. 
> >>>>> 
> >>>>> The preliminary copy of the paper is at http://www.rlgsc.com/publications/openvmsstartupunderappreciatedflexibility.html. 
> >>>>> 
> >>>>> - Bob Gezelter, http://www.rlgsc.com 
> >>>> Bob it is a very complete writing, I thank you very much for the time you invest in this type of research and share it with the community. I appreciate it. 
> >>>> 
> >>>> very thankful 
> >>> Edgar, 
> >>> 
> >>> You are welcome. My pleasure. 
> >>> 
> >>> Since I posted the paper. I identified several errata. I corrected them and posted a revised copy (Revision 2020-12-06). 
> >>> 
> >>> - Bob Gezelter, http://www.rlgsc.com 
> >>> 
> >> "Errata"? 
> >> 
> >> Is that the replacement word for "mistake"? 
> >> 
> >> :-) 
> >> 
> >> -- 
> >> David Froble Tel: 724-529-0450 
> >> Dave Froble Enterprises, Inc. E-Mail: da... at tsoft-inc.com 
> >> DFE Ultralights, Inc. 
> >> 170 Grimplin Road 
> >> Vanderbilt, PA 15486 
> > David, 
> > 
> > "Mistake" is singular. Errata is the plural of erratum. 
> > 
> > - Bob Gezelter, http://www.rlgsc.com 
> >
> Ok, then, "mistakes" ... 
> 
> Since you took the time to write, I decided I should at least devote the 
> time to read. It is not something that most users will need to know 
> about, but, knowledge is usually a good thing. 
> 
> Overall, a nice description of the processing. 
> 
> One thing I noticed by it's omission. That is the admonishment to 
> strictly stay out of the VMS startup procedures as much as possible. It 
> is my firm belief that applications and users should have a different 
> place than the OS startup. At most the system startup could invoke user 
> and application startups. 
> 
> As an example, I use a separate batch job to start up DECnet, LAT, and 
> TCP/IP. I also use separate command files to startup applications. 
> Prior to this, it is possible for an operator login on OPA0, should that 
> be required. 
> 
> Just my opinion, namely, "stay out of the OS stuff".
> -- 
> David Froble Tel: 724-529-0450 
> Dave Froble Enterprises, Inc. E-Mail: da... at tsoft-inc.com 
> DFE Ultralights, Inc. 
> 170 Grimplin Road 
> Vanderbilt, PA 15486
David,

Thank you for taking the time to read the whitepaper.

Your question is a good one. The "admonishment to strictly stay out of the VMS startup procedures as much as possible" is omitted because with the exception of VMS$VMS.DAT, the facilities are deliberately designed and implemented to be used by layered product, ISVs, and end-user administrators. Were that not so, file names would be hardwired and SYSMAN would not have the commands to manipulate the data contained in the databases. As the paper noted, adding components to be part of the startup sequence is documented, although the documentation is not as clear as it could be.

Documented facilities used within their design intent are always permissible. The facilities of STARTUP.COM and SYSMAN are as much a part of supported OpenVMS as SYS$QIO, SYS$WAIT, and other system services.

Using LAT and TCP/IP as examples, the appropriate startup files are easily added to VMS$LAYERED.DAT, so long as the prerequisites are satisfied. In this particular case, since DECnet changes the MAC address, DECnet (Phase IV or Phase V) must be started before LAT and TCP/IP. There is no dependency relationship between LAT and TCP/IP, so they can be started during the same phase. Thus, I add LAT$STARTUP.COM and the appropriate TCP startup file as SPAWN mode after DECnet has been started. NET$STARTUP.COM is invoked fairly early in the STARTUP sequence.

STARTUP.COM could automatically submit batch jobs under SYSTEM, but I generally prefer SPAWN, since a batch job could get hung. 

Similarly, ENABLING/DISABLING entries in the Startup database is simple, using the SYSMAN STARTUP ENABLE/DISABLE commands. Far less error prone than manual editing.

My preference is to avoid manual intervention during system/application startup. Manual intervention is far too often a source of problems.

- Bob Gezelter, http://www.rlgsc.com