[Samba] AD DCs and LDAP query 'stalls'...

[Marco Gaiarin]

Sometime i hit this, that, i admit, it is hard to debug.

Situation: an AD domain, 4 sites, 6 DCs, sorry but samba 4.9.18+dfsg-0.1stretch1
(louis packages).

In this domain i do extesively LDAP query on the DC, eg using it inside
other software (eg, exim), or using scripts (bash wrappers around
ldbsearch).

Sometimes a DC 'stalls': exim query simply fail (so email get bounced),
ldbsearch that seems have not a timeout simply stalls and pile up.
If i reboot the DCs (that, inded, for other things: DNS resolving, ...
seems to wok as expected), all come back to normal.

For now i've programmed a weekly reboot of my DCs. But i'm curious why only
the LDAP query seems stall...


Ah, one more note: a thing that seems to trigger this.
2 DCs are behind a private wireless link that sometime suffer failure,
clerly on non-working hour; if these DC get isolated, after some hours one
of the other DCs stall: most probably the DC with FSMO role, but not
everytime (there are other DCs 'nearest' in domain topology).


Thanks.

-- 
  Ognuno vada dove vuole andare, ognuno invecchi come gli pare
  ma non raccontate a me che cos'e` la LIBERTA`.	(F. Guccini)