Using CIFS for Windows Access
System Administration Manual
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By default, when authenticating clients in an Active Directory, Titan uses the time maintained
by the domain controller, automatically adjusting for any clock inconsistencies.
Dynamic DNS
On TCP/IP networks, servers communicate with each other through their IP addresses. The
Domain Name System (DNS) is the most common method by which clients on a network or on
the Internet resolve a host name with an IP address, facilitating IP-based communication
between them.
With DNS, records must be created manually for every host name and IP address. Starting with
Windows 2000 Microsoft enabled support for Dynamic DNS, a DNS database which allows
authenticated hosts to automatically add a record of their host name and IP address,
eliminating the need for manual creation of records.
Registering a name
When an EVS goes online, Titan registers each configured ADS CIFS name and IP address
associated with the EVS with the
configured DNS servers
. One entry will be recorded in DDNS
for every configured IP address. If a server has more than one configured ADS CIFS name, an
entry for each IP address for each configured CIFS name will be registered. Registrations are
made to both forward and reverse lookup zones.
Each hostname registered with the DNS server has a Time To Live (TTL) property of 20 minutes,
which is the amount of time other DNS servers and applications are allowed to cache it. In other
words, the DNS server uses a cache file to retain a copy of the DNS lookup details for 20
minutes. The record's TTL dwindles with passing time and when the TTL finally reaches zero,
the record is removed from the cache. After the 20-minute expiration point, the client must
execute a fresh name lookup for more information.
The hostname is refreshed every 24 hours. This refresh commences after the first successful
registration. For instance, if Titan registers its name at bootup, then every 24 hours after the
bootup it
refreshes
its DNS entry. If Titan cannot register or refresh its name, it goes into
recovery mode with an attempt to register every 5 minutes. Once it successfully registers, it will
resume the 24 hours-per-refresh cycle.
Secure DDNS Updates
Titan supports both secure and insecure DDNS updates. By default, Microsoft Windows 2000
and 2003 DDNS servers only accept “secure”, Kerberos-authenticated registrations. To support
both Microsoft and non-Microsoft DDNS servers, Titan will first attempt to register with DDNS
insecurely. If the insecure registration fails, Titan will attempt a secure registration.
CIFS Statistics
Statistics
are available to monitor CIFS activity since Titan was last started or its statistics were
reset. The statistics are updated every ten seconds.
