smbwall

[David Lee]

On Thu, 31 Jan 2002, Andrew Morgan wrote:

> On 31 Jan 2002, Scott Gifford wrote:
> 
> > "Garry J. Garrett" <garry_garrett at csgsystems.com> writes:
> >
> > [...]
> >
> > > My point is, I'm sure that there is a limitation somewhere; we just
> > > don't know what that limit is.  It may be smaller than you are inclined
> > > to think at first glance.  That's all I'm trying to say.
> >
> > I'm sure this is true, but as long as it can easily be turned off with
> > an smb.conf option, it should be OK.  If you have more smbds than
> > ptys, you just don't configure Samba to allocate ptys.
> >
> > Do you see any problems with this approach?
> 
> It seems like this could really bite someone though.  What if over time
> you start getting more samba connections?  Sometimes it is not possible to
> plan ahead for this situation either.  I don't really know, but it seems
> like running out of ptys would be a very bad thing.

That used to be the case for telnet/rlogin under early Solaris some years
ago (default of 48; caller 49+ would get obscure failure message).  But
that limit was always configurable, and since those days they seem to be
much more "dynamic" anyway.  (Yes, it used to cause an irritating
"Grrrrr..." moment to me, as sys.admin., but I've seen worse problems in
running a UNIX service!)

I suspect that on most modern-day UNIX systems, a permanent, unchangeable,
never-any-higher limit on ptys is almost a non-issue.  And for the
occasional system where it may be, then ...

> I'm in favor of another approach someone else mentioned: just allocate one
> pty for all the smbds.  You can't send individual messages then, but it
> covers the wall/shutdown case nicely.

It isn't necessarily either/or.  For instance, we could code to permit
full 1:1 pty-per-smbd flexibility or single 1:many pty-all-smbds.  The
code would certainly be flexible enough to allow a "wall-listener" daemon
to be built where prefered or necessary at a site.  The configuration of
this could be variable, both at "configure" time and "smb.conf" time. 


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