Managing the database servers

Once the database file has been created, the server must be configured for this file. This is done using a NAMES file, as follows.

Names file entries for a database file (hepdb.names)

:nick.config
            :list.ge au
            :log./hepdb/cplear/logs
            :queue./hepdb/cplear/queue
            :todo./hepdb/cplear/todo
            :save./hepdb/cplear/save
            :bad./hepdb/cplear/bad
            :loglevel.3
            :wakeup.60
            :servers.cernvm vxcpon hepdb

:nick.ge
            :file./hepdb/cplear/database/geo.dbs
            :servers.vxcpon hepdb cernvm
            :desc.Geometry database for the CPLEAR experiment

:nick.au
            :file./hepdb/cplear/database/aux.dbs
            :servers.vxcpon cernvm
            :desc.Auxiliary database for the CPLEAR experiment
            :read.*
            :write.phr cpb

:nick.hepdb
            :userid.cdcplear
            :node.hepdb
            :localq./hepdb/l3/todo

:nick.vxcpon
            :userid.cdcplear
            :node.vxcpon
            :queue.disk$db:[cdcplear.todo]
            :protocol.tcpip
            :localq./hepdb/cplear/tovxcpon

:nick.cernvm
            :userid.cdcplear
            :node.cernvm
            :queue./hepdb/cplear/tocernvm
            :protocol.tcpip
            :localq./hepdb/cplear/tocernvm

The various tags in the preceding names file have the following meanings.

CONFIG

Configuration details for the server, as follows.

LIST

A list of two character database prefixes

LOG

The directory where the server logs are written

QUEUE

The directory where new updates are placed by HEPDB clients

TODO

The directory scanned by the HEPDB servers for updates to process. In the case of MASTER servers, the todo and queue directories are the same. In the case of SLAVE servers, these queues are different.

BAD

The directory where the server places bad updates. Bad updates are files for which the corresponding database cannot be found, or updates which cannot be successfully processed by the database server.

SAVE

The directory where the server saves updates after processing

LOGL

The log level for the server

WAKEUP

The wakeup interval in seconds for the server

SERVERS

This is the or of the list of servers for the individual databases. The database servers are responsible for moving updates to the local queues for the remote servers. A separate process, CDMOVE, is responsible for moving the processes between different systems.

prefix

The two character database prefix, e.g. aa.

FILE

The full name of the database file. For VM/CMS systems, the syntax is <user.address>filename.filetype

DESC

A comment string identifying the database and/or its purpose

SERVERS

The list of remote servers for this database. Each node in this list must also be in the list for the :nick.config entry.

READ

A list of users who may read the database. An asterisk grants read access to all users. If this tag is not present, read access control is not performed.

WRITE

A list of users who may update the database. Users with write access automatically gain read access. If this tag is not present, write access control is not performed.

server

The nickname of the servers, e.g. aa1.

USERID

Userid under which the server runs on the remote node

NODE

Node on which the server runs

QUEUE

Input queue on the remote node

PROTOCOL

Method by which updates are transmitted

LOCALQ

The local directory where updates are written pending transmission to the remote node. This may, in fact, be the same as QUEUE, e.g. when the directory is accessible via NFS or AFS.   

• Master and slave database servers