It is possible to install multiple replicators on the same host. This can be useful, either when building complex topologies with multiple services, and in hetereogenous environments where you are reading from one database and writing to another that may be installed on the same single server.
When installing multiple replicator services on the same host, different values must be set for the following configuration parameters:
Before continuing with deployment you will need the following:
The name to use for the service.
The list of datasources in the service. These are the servers which will be running MySQL.
The username and password of the MySQL replication user.
All servers must be prepared with the proper prerequisites. See Appendix B, Prerequisites for additional details.
RMI network port used for communicating with the replicator service.
Set through the --rmi-port parameter
to tpm. Note that RMI ports are configured in
pairs; the default port is 10000, port 10001 is used automatically.
When specifying an alternative port, the subsequent port must also be
available. For example, specifying port 10002 also requires 10003.
THL network port used for exchanging THL data.
Set through the --thl-port parameter
to tpm. The default THL port is 2112. This option
is required for services operating as Extractors.
Extractor THL port, i.e. the port from which an Applier will read THL events from the Extractor
Set through the --master-thl-port
parameter to tpm. When operating as an Applier, the
explicit THL port should be specified to ensure that you are
connecting to the THL port correctly.
Extractor hostname
Set through the --master-thl-host
parameter to tpm. This is optional if the Extractor
hostname has been configured correctly through the
--master parameter.
Installation directory used when the replicator is installed.
Set through the --install-directory
or --install-directory parameters to
tpm. This directory must have been created, and be
configured with suitable permissions before installation starts. For
more information, see Section B.3.4, “Directory Locations and Configuration”.
For example, to create two services, one that reads from MySQL and another that writes to MongoDB on the same host:
Install the Tungsten Replicator package or download the Tungsten Replicator tarball, and unpack it:
shell> cd /opt/continuent/software
shell> tar zxf tungsten-replicator-7.1.4-10.tar.gzCreate the proper directories with appropriate ownership and permissions:
shell> sudo mkdir /opt/applier /opt/extractor
shell> sudo chown tungsten: /opt/applier/ /opt/extractor/
shell> sudo chmod 700 /opt/applier/ /opt/extractor/Change to the Tungsten Replicator directory:
shell> cd tungsten-replicator-7.1.4-10Extractor reading from MySQL (Click link to switch examples between Staging Method or INI Method):
shell> vi /etc/tungsten/tungsten.ini[defaults]
install-directory=/opt/extractor
user=tungsten
profile-script=~/.bash_profile
mysql-allow-intensive-checks=true
disable-security-controls=true
executable-prefix=ext
rest-api-admin-user=apiuser
rest-api-admin-pass=secret
[alpha]
master=offboardhost
members=offboardhost
enable-heterogeneous-service=true
replication-port=3306
replication-user=tungsten_alpha
replication-password=secret
datasource-mysql-conf=/etc/my.cnf
svc-extractor-filters=colnames,pkey
property=replicator.filter.pkey.addColumnsToDeletes=true
property=replicator.filter.pkey.addPkeyToInserts=true
mysql-enable-enumtostring=true
mysql-enable-settostring=true
mysql-use-bytes-for-string=falseConfiguration group defaults
Configuration group alpha
This is a standard configuration using the default ports, with the
directory /opt/extractor.
Applier for writing to MongoDB (Click link to switch examples between Staging Method or INI Method):
shell> vi /etc/tungsten/tungsten.ini[defaults]
install-directory=/opt/applier
profile-script=~/.bash_profile
skip-validation-check=InstallerMasterSlaveCheck
executable-prefix=app
rest-api-admin-user=apiuser
rest-api-admin-pass=secret
[alpha]
master=localhost
members=localhost
role=slave
datasource-type=mongodb
replication-user=tungsten
replication-password=secret
rmi-port=10002
master-thl-port=2112
master-thl-host=localhost
thl-port=2113Configuration group defaults
Configuration group alpha
In this configuration, the Extractor THL port is specified explicitly,
along with the THL port used by this replicator, the RMI port used for
administration, and the installation directory
/opt/applier.
Run tpm to install the software
shell > ./tools/tpm install
During the startup and installation, tpm will
notify you of any problems that need to be fixed before the service
can be correctly installed and started. If
start-and-report is set and the
service starts correctly, you should see the configuration and current
status of the service.
Initialize your PATH and environment.
shell > source /opt/extractor/share/env.sh
shell > source /opt/applier/share/env.sh
Check the replication status.
When multiple replicators have been installed, checking the replicator
status through trepctl depends on the replicator
executable location used. If
/opt/extractor/tungsten/tungsten-replicator/bin/trepctl,
the extractor service status will be reported. If
/opt/applier/tungsten/tungsten-replicator/bin/trepctl
is used, then the applier service status will be reported.
To make things easier, in the config examples above
executable-prefix has been used, which will
set up OS aliases. These aliases are setup when you source the relevant
env.sh files, this will also happen by default when you
login to the host providing profile-script
has been specified
The use of the prefix and aliases, then simplifies the use of all
executables, for example, based on the setting of
executable-prefix in the above config
examples, to report the status of the extractor, you
can execute:
shell> ext_trepctl statusOr to check the applier service:
shell> app_trepctl statusAlternatively, a specific replicator can be checked by explicitly specifying the RMI port of the service. For example, to check the extractor service:
shell> trepctl -port 10000 statusOr to check the applier service:
shell> trepctl -port 10002 statusWhen an explicit port has been specified in this way, the executable used is irrelevant. Any valid trepctl instance will work.
Further, either path may be used to get a summary view using multi_trepctl:
shell> /opt/extractor/tungsten/tungsten-replicator/scripts/multi_trepctl
| host | servicename | role | state | appliedlastseqno | appliedlatency |
| host1 | extractor | master | ONLINE | 0 | 1.724 |
| host1 | applier | slave | ONLINE | 0 | 0.000 |