OSF DCE Administration Guide--Core Components

Managing the DCE DST

Whenever the system cannot contact the number of servers speciﬁed by the minservers

attribute setting, the system increments the toofewservers counter, logs the event, and

displays the event message Too Few Servers Detected. Information included in the

event message shows the number of servers that are currently available and the number

required. If you see this event message displayed, check whether any of the servers have

failed, test the communications links to ensure that the system has not been isolated from

the servers, or add servers to the network.

You can use the minservers attribute in other ways, depending on your network

conﬁguration. Consider the following cases:

• If you have only a few systems in your network and you want to synchronize the

nodes regardless of server drift, lower the minservers attribute value to 1 or 2 .

Although the resulting synchronized time is a less reliable measure of UTC, you

increase the likelihood that the systems will synchronize. If the setting is less than 3,

however, the system cannot identify faulty servers. Subsequent server clock drift

causes divergence from UTC.

• To increase fault tolerance and ensure that the systems compute reliable times, set

the minservers attribute value to 3 (the default setting) or higher. The systems can

then identify faulty servers and compute the narrowest overlapping interval for the

time values that they receive. Remember, however, that your system will not

synchronize until there are at least three servers available.

The number of nodes in your network and the types of applications that you use

determine whether guaranteed synchronization or reliable times and fault tolerance are

more important.

25.5.2 Use of minservers Attribute with Global Servers

If your network consists of more than a single LAN, it should have a set of global

servers. You can create global servers by advertising local servers to the cell proﬁle.

(See Section 25.6.1.1 for further information.)

The presence of global servers in your network can inﬂuence the value that you choose

for the minservers attribute. If the number of local servers available to a clerk or server

is less than the minservers attribute setting, the clerk or server automatically searches

the cell proﬁle for a global server name. The clerk or server then requests time values

from the global and local servers.

You can check to see whether global servers exist by entering the dts show command

and viewing the globalservers attribute value. The dts show command can be entered

with options (-attributes or -all) or without any options, as follows:

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