agismail/zkuacoordination

Distributed Coordination of Redundant OPC UA Servers with Apache ZooKeeper

Coordinating Redundant OPC UA Servers

This code accompanies the IEEE ETFA'17 paper "Coordinating Redundant OPC UA Servers". The paper is available under the docs folder and explains the architecture, data model, and implementation.

This code is for PoC purposes and should not be used in production.

Compiling

Based on a debootstrapped debian stretch VM:

Dependencies:

apt-get install -y dh-autoreconf wget make git openjdk-8-jdk libcppunit-dev libcppunit-doc libtool patch libzookeeper-mt-dev libjansson-dev

Compile:

ACLOCAL="aclocal -I /usr/share/aclocal" autoreconf -if
./configure && make

Running a zkUA Client, Server, Failover Controller

The ZooKeeper server/quorum should already be running.

Configure the zkUA configuration file (clientConf.txt and or serverConf.txt) and execute as so:

./cli_mt_UA_client
./cli_mt_UA_server
./cli_mt_UA_failoverController

The server should be started before the failoverController.

Dockerfile

Build the docker image using:

docker build -t zkua .

Alternatively pull the image from:

docker pull amismail/zkuaRedundancy

Run the docker container using the command:

docker run -it -p 16664:16664 --name zkua_1 zkua /bin/bash

Port 16664 is the default port configured in serverConf.txt for the zkUA Server. This is the port you connect to using a zkUA Client or UA Client (e.g., using UA Expert).

NOTE: You will need a ZooKeeper cluster running - update the config files with ZooKeeper's IPs and port numbers accordingly.

Limitations

Currently, the code is limited to replicating nodes with a namespace Index > 0 and nodes with numeric identifiers.

Methods are not replicated.