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The dbrepl configuration file is used to specify the configuration and
defaults of a database replication instance. It is read by the dbrepl utility
on startup.
Configuration items contain information in the form of single lines of text.
Lines starting with a hash character (#) are comments.
The following configuration items are recognized:
Settings in the config file may be replaced using the equivalent
dbrepl command line options.
Supported configuration items:
- primary
-
The config file of the replication primary database server.
An absolute path/file name or a file name relative to the Eloquence config
directory. If not specified, the default eloqdb.cfg is used.
primary = eloqdb.cfg
The dbrepl -c option may be used as an
alternative to specify the primary server config file.
- secondary
-
The secondary server host name or IP address and service name or port number,
separated by a colon ([host][:service]). If not specified, the secondary server
address defaults to the EQ_DBSERVER environment variable or
localhost:eloqdb.
secondary = localhost:eloqdb
The dbrepl command line may be used to
specify the secondary server.
- dbuser
dbpassword
-
Database credentials (may also reference a file).
If not specified, the database credentials default to the EQ_DBUSER
and EQ_DBPASSWORD environment variable or the dba user.
dbuser = dba
The dbrepl -u and -p options may be used
as an alternative to specify the user and password.
- logfile
-
Specifies the log file (absolute path) or "syslog" to use syslog.
Defaults to stderr when used interactively and syslog when used
in background.
logfile = syslog
The dbrepl -l option may be used as an
alternative to specify the log file.
- logflags
-
Specified the log flags. Log flags "*0" indicate error messages,
Log flags "*1" log error messages and warnings.
Default log flags is "*0", log flags *1 is recommended.
logflags = *0
The dbrepl -d option may be used as an
alternative to specify the log flags.
- sysident (HP-UX, Linux)
sysfacility (HP-UX, Linux)
-
When logging to syslog this defines the syslog identity and facility.
The default is identify = dbrepl and facility = user.
sysident = dbrepl
sysfacility = user
- retrycnt
retrydelay
-
Retry secondary server connection after a connection failure (retry limit
and delay in seconds).
retrycnt = 0
retrydelay = 300
The dbrepl utility supports retrying after a secondary server connection
failure. This functionality is enabled with the RetryCnt and
RetryDelay config items (there is no corresponding command
line option).
RetryCnt specifies the max. number of retries and
RetryDelay the delay in seconds between each attempt.
The default RetryCnt is 0 (no retries), the default
RetryDelay is 300 seconds (5 minutes).
- bandwidthlimit
-
Limit bandwidth to specified [kilo|mega] bits per second.
A unit "m" (mega) or "k" (kilo) may be appended to the value.
For example, 10m specifies 10 million bits per second.
bandwidthlimit = 0
This may be used to limit the network bandwidth consumed by the replication.
A throttling may be useful in case the network link between primary and secondary(s)
is not dedicated to dbrepl and should not be saturated by the replication
during high activity periods on the primary.
The dbrepl -b option may be used as an
alternative to specify the bandwidth limit.
- compression
-
If set to a nonzero value enables compression to be used for
replication if supported by secondary server.
Compression may improve performance when replicating over WAN
connections but is less likely to be helpful for LAN connections.
compression = 0
- buffersize
-
Specifies the communication buffer size (default: 32000 bytes).
A higher buffer size may improve replication throughput in high
latency network environments (WAN).
Network latency limits the number
of client/server transactions per second.
For example, a latency of 20 ms means a maximum of 50 transactions
per seconds, which in turn limits replication throughput to 1.6 MB
per second given the default buffer size (50 * 32000 bytes).
Unit m (mega) or k (kilo) may be appended to the value.
For example, 100K specifies a buffer size of 100*1024=102400 bytes.
The max. buffer size is 1M (1048576 bytes).
buffersize = 32000
Changes
The B.08.30 release added support for compression and configurable
transfer buffer size.
As of B.08.40 the designation of replicated servers and roles was
updated. A master server is now described as primary server and a
former slave server is now described as a secondary server or a
replicated server.
This affects any messages and configuration options. Any previous
config files are fully compatible.
repl.cfg template file
A default configuration file repl.cfg is installed and may be customized.
It is recommended to use a separate replication config file for each
replication instance. A template replication config file is installed
as newconfig/config/repl.cfg.
# @(#) repl.cfg - B.08.40 ($Revision: 29.2 $)
#
# This file configures a replication instance and is read by dbrepl.
# Default location is the /etc/opt/eloquence/8.4 directory
# The primary database config file
# Absolute path or relative to the Eloquence config directory
#primary = eloqdb.cfg
# The secondary server [host][:service]
#secondary = localhost:eloqdb
# database credentials (may also reference a file)
#dbuser = dba
#dbpassword =
# syslog identity and facility
#sysident = dbrepl
#sysfacility = user
# specifies the log file (absolute path) or "syslog" to use syslog
# defaults to stderr when used interactively and syslog when used
# in background.
#logfile = syslog
# log flags, recommended is *1
#logflags = *0
# retry after connection failure (retry limit and delay in seconds)
#retrycnt = 0
#retrydelay = 300
# limit bandwidth to specified [kilo|mega] bits per second
# unit m (mega) or k (kilo) may be appended to the value
# for example, 10m specifies 10 million bits per second.
#bandwidthlimit = 0
# If set enables compression to be used for replication if
# supported by secondary server. compression may improve performance
# when replicating over WAN connections but is less likely to be
# helpful for LAN connections.
#compression = 0
# Specifies the communication buffer size (default: 32000 bytes).
# A higher buffer size may improve replication throughput in high
# latency network environments. Network latency limits the number
# of client/server transactions per second. For example, a latency
# of 20 ms means a maximum of 50 transactions per seconds, which
# in turn limits replication throughput to 1.6 MB per second given
# the default buffer size (50 * 32000 bytes).
# Unit m (mega) or k (kilo) may be appended to the value.
# For example, 100K specifies a buffer size of 100*1024=102400 bytes.
# The max. buffer size is 1M (1048576 bytes).
#buffersize = 32000
dbrepl utility
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