Possible to have a nodename greater than 6 characters?

[Jim Geier_1]

While perusing and searching the OpenVMS forums, I saw a posting discussing a system fatal bugcheck crash that showed a 12 and 14-character nodename:

%SYSBOOT-W-WS default and quota raised to PHD+MINWSCNT
VAX/VMS Version V5.5-2 Major version id = 1 Minor version id = 0

%CNXMAN, Using remote access method for quorum disk
waiting to form or join a VAXcluster system
%CNXMAN, Sending VAXcluster membership request to system FREDFLINTSTONE
%CNXMAN, Now a VAXcluster member -- system BARNEYRUBBLE

There are other entries in the text that give additional, seemingly credible evidence that the systems have node names longer than 6 characters.

%%%%%%%%%%% OPCOM 21-MAY-2004 06:36:23.66 %%%%%%%%%%%
Logfile has been initialized by operator _BARNEYRUBBLE$OPA0:
Logfile is BARNEYRUBBLE::SYS$SYSROOT:[SYSMGR]OPERATOR.LOG;24

Is there (or since this was a V5.5-2 system, was there) some means of getting around the limit of 6 characters for the SCSNODE parameter? Or was the entry that I saw edited?

[Uwe Zessin]

My guess is that were made-up entries.

On the other hand, it looks like _some_ locations in SCA can work with names longer than 6 characters. If I recall correctly, the maximum buffer size for SYS$GETSYI[W] (SYI$_NODENAME) can be 16 characters.

For example, I have seen DSSI disks with an 8-character nodename, but those disks have never been cluster members ;-)

[Mobeen_1]

Jim,
To put it in simple terms the answer would be NO. Atleast in my stint of 12 yrs i have not come across one at various sites.

Even if its possible, i am not sure with what risks that could be done. I am sure lot of our experienced colleagues will jump in with their experiences and i am waiting for that :)

rgds
Mobeen

[Volker Halle · Accepted solution]

Jim,

the SCSNODE system parameter is stored in a quadword (SCS$GB_NODENAME), so there is only room for 8 characters.

Just setting it to 8 chars with SYSGEN works on OpenVNS VAX V6.2, but not on OpenVMS Alpha E8.2 anymore (returns %SYSGEN-E-STRTOOLNG). Try it on your favourite version of OpenVMS, but don't use SYSGEN> WRITE CURRENT afterwards ;-)

There will be some code, which makes some assumptions, which you are going to break, if you make SCSNODE longer than 6 chars. Why not try it, then you can find out and tell us ?

Volker.

[Michelle Popejoy]

As I recall, the major factor limiting nodename to 6 characters was DECnet.

[Ian Miller.]

DECnet /Plus allows longer names. SCSNODE does not

[Kris Clippeleyr]

Jim,

According to the manual
http://h71000.www7.hp.com/doc/731FINAL/4477/4477pro_013.html#build_cluster
the SCSNODE parameter cannot exceed 6 characters in length; the same goes for the DECnet phase IV nodename. I think the restriction on the length of the SCSNODE parameter indeed stems from the days where we had to have DECnet (still phase IV at that time) to run our clusters.

Regards,
Kris (aka Qkcl)

[Jess Goodman]

I can set SCSNODE to 8 characters, but not 9, on my V6.2 and V7.2 Alphas.

When testing this I noticed something about the SYSGEN utility that had escaped my attention in the 20 years I've been working on VMS. It apparently uses the terminal driver's IO$M_CVTLOW modifier to upcase all input as you enter it - whatever you type at the SYSGEN> prompt will be echoed in uppercase. I was trying to enter the dummy string "zzzzzzzz" for SCSNODE and I thought the caps key on my keyboard had broke. I don't think there's any other VMS utility that does this.

SYSMAN's PARAMETER SET command converts a string to uppercase too, but only AFTER you enter it.

[John Gillings]

Jim,

Unfortunately OpenVMS "nodename" is an overloaded term. There are several places that *a* name can be assigned. In practice you should make sure they all agree.

Back in the V5 timeframe, there were efforts made to increase the length of some fields. For example, USERNAME from 12 to 32 and various others. It was found there were too many places that made assumptions about name length and it was all too hard to fix, so a few "blade guards" were put in place to maintain the old limits, even though there are many code paths that can tolerate the higher limits. There are ways of subverting these guards to exceed the supported limits for things like username. They mostly work, but some things break (for example, MAIL will not work for a username with >12 characters, but most other things will)

If you don't run DECnet, I believe you can define an SCSNODE to 8 characters. It should work, but please don't complain if something breaks!