[Info-vax] Unexpected DECnet Phase IV functionality with possible captive account implications

[Arne Vajhøj]

On 5/11/2021 4:57 PM, Stephen Hoffman wrote:
> On 2021-05-11 18:30:01 +0000, Dave Froble said:
>> Which of them allow:
>>
>> Open "DFE90A::[DFE]DATA.DAT" For Input as File #1%
>>
>> Assuming proxys are set appropriately.
>>
>> Please don't reply with:
>>
>> Open "DFE90A"DFE XXX"::[DFE]DATA.DAT" For Input as File #1%
>>
>> If I even remember how to do that correctly ...
> 
> What you're doing with RMS and FAL is entirely feasible, though through 
> different means.
> 
> MOUNT the remote system, and access it locally. With newer systems, 
> that'd usually be an SMB mount, though OpenVMS lacks modern storage 
> connections. On OpenVMS, it'd be NFS, or maybe DFS. Then aim SQLite at 
> it, etc.
> 
> Or with newer applications, the access would be ODBC, or a message 
> queue, or—closest to what you're doing—with the database directly e.g. 
> MariaDB and the mysql -u RemoteUser -p -h 203.0.113.13 command, etc.

There are obviously many ways to access data on other servers.

But neither the ability to mount a remote file system or access
a remote database server is a 1:1 substitute for transparent
file access to remote file system.

> This whole area—FAL, RMS, the file system itself, remote mounts, 
> database support—is dated, as compared with the other platforms many of 
> us are now working with.
> 
> And in more general terms, I am un-fond of exposing the database 
> structures remotely whether by classic FAL and RMS or file share or 
> otherwise, as that makes modifications more difficult. Modifying an RMS 
> database when its internal structures have escaped the API layer and 
> becomes known to apps is un-fun. q.v. SYSUAF.DAT, etc. Which further 
> reduces my interest in using FAL and RMS, beyond discussions of the 
> authentication and encryption issues. And anybody still using FAL and 
> RMS and DECnet almost assuredly already knows about this difficulty.
> 
> My preference would be to move out of RMS for storage for many 
> production apps, though that migration is less than easy for entrenched 
> configurations, and any migration necessarily incremental for many.

If one starts with a blank piece of paper, then relying on
files in the file system is likely not a good choice. Bad
scalability, bad performance etc.. Some sort of database
(RDBMS or NoSQL DS or NoSQL KVS) will typical be much better.

But in the real world starting with a blank piece of paper
is pretty rare.

Arne