Caché System Administration Guide - InterSystems Documentation

Using Caché on UNIX, Linux, and Mac OS X
6.2.4.2 Step 2. Perform Recovery
The startup script tests for the existence of the CACHE.WIJ file in the install-dir/mgr directory:
• If the CACHE.WIJ file does not exist, startup proceeds to Step 3.
• If the CACHE.WIJ file does exist, the startup script runs the recovery program (cwdimj). The
recovery program checks for the existence of the ids shared memory object:
- If the ids shared memory object exists, the system is assumed to be up and running. The
recovery program exits with an error. Startup halts.
Action: The user must run cstop or cforce to halt the running instance.
- If the ids shared memory object does not exist, the recovery program checks the Daemon
Resource Locks:
• If no Daemon Resource Locks are held, recovery assumes Caché is not running. The
recovery process locks the Control Process Resource Lock to prevent concurrent startups,
and performs recovery on the instance. When the process exits, the lock is released, and
startup continues with Step 3.
• If Daemon Resource Locks are held, one or more daemons are running on some node
for this instance. The recovery program reports this and exits with an error. Startup halts.
Action: The user must run cstop or cforce to halt the running instance on the appropriate
node. This deletes the cache.ids file and the ids shared memory object.
6.2.4.3 Step 3. Start Caché
The Caché startup process (cache) is run. Checks are repeated to ensure that another startup is not
competing for the startup resources:
• If Daemon Resource Locks are held, indicating one or more daemons are running on some node
for this instance, Caché reports this and exits with an error. Startup halts.
The node on which the daemons are running is unknown if the cache.ids file does not exist.
Action: The user must assume that another startup has occurred on some node. To determine on
which node the instance has started, examine the cache.ids file.
Caché continues startup. At the end of the first phase (Control process startup and daemon initialization),
shared memory, the ids shared memory object, and the cache.ids file are created.
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