Pathway/XM System Management Manual

Managing Servers
Compaq NonStop™ Pathway/XM System Management Manual—426761-001
9-4
Freezing and Thawing Server Classes
queued for the time period specified by the CREATEDELAY attribute for the server
class.
A link manager always tries to satisfy a send request with a static link if one is available.
If a dynamic server process sits idle for the time limit defined by the DELETEDELAY
attribute for the server class, the link manager returns the link to the PATHMON
process.
You determine the number of dynamic servers for a server class with the SET SERVER
MAXSERVERS and SET SERVER NUMSTATIC attributes. If MAXSERVERS is 4
and NUMSTATIC is 2, this server class can have two dynamic servers.
Link Requests
If the PATHMON process gets a link request from a link manager to a server class, and
the server class is not frozen but no server processes have been started, the PATHMON
process starts only the server process that satisfies the link manager’s request; it does not
start all of the static server processes in the server class.
Freezing and Thawing Server Classes
To disable communication from LINKMON processes and TCPs to server processes
without actually stopping the server class, use the FREEZE SERVER command. The
FREEZE SERVER command prevents LINKMON processes and TCPs from sending
requests to the server processes. The THAW SERVER command reverses the effect of
the FREEZE SERVER command.
The FREEZE SERVER and THAW SERVER commands can be used with all types of
server classes: distributed, direct, and replicated. For the syntax of these commands,
refer to FREEZE SERVER
on page 11-24 and THAW SERVER on page 11-106.
For example, the following command freezes all server processes in the server class
SALES:
>> FREEZE SERVER SALES
If no server process in the server class has incomplete or outstanding requests, the
PATHMON process freezes the server class immediately. If any server process in the
server class has incomplete or outstanding requests, the PATHMON process does not
freeze the server class until these requests are completed. While awaiting completion of
such requests, the server class remains in the FREEZE-PENDING state and can accept
no new requests.
You can tell the PATHMON process to ignore the STOPMODE register, even if it is
set, by terminating the FREEZE SERVER command with an exclamation point, as
shown in the following example:
>> FREEZE SERVER SALES!
Keep in mind that some outstanding requests might not be fulfilled. (If the TMF
subsystem is running, transactions in process are backed out as part of the freeze.)