How to Install Exalate for ServiceNow on Docker

    You can host Exalate for Servicenow on your own server. To do so, you need to install Exalate on Docker.

    Note: You need to install Docker. Check the docker documentation for more details.

    How to Install Exalate for ServiceNow

    1. Create directory and create docker-compose.yml file

    Create a directory to hold the docker-compose file:

    cd ~
    mkdir exalate-snownode

    Create or download a docker-compose.yml file.

    Note: Click docker-compose.yml to download the file.

    Important: We recommend using the latest version of Exalate for ServiceNow. It can be found in the Release History.

    Enter the latest version in the image tag. For example, in image: idalko/snownode:5.6.0, the version of Exalate for ServiceNow is 5.6.0 .

    The docker-compose.yml file should contain the following information in it:

    version: '2'
    
    services:
      database:
        restart: unless-stopped
        image: postgres:9.4
        volumes:
          - ./persist/db:/var/lib/postgresql/data
          - ./createdb.sh:/docker-entrypoint-initdb.d/init-user-db.sh
        environment:
          - POSTGRES_PASSWORD=changeme
          - DB_NAME=snownode
          - DB_USER=idalko
          - DB_PASS=idalko
        networks:
          - dbnet
    
      snownode:
        restart: unless-stopped
        ports:
          - 9000:9000
    
        #
    	# Change the image tag to the required version
        # Check Release History on docs.exalate.com for an overview
        #
        image: idalko/snownode:5.6.0
        depends_on:
          - database #wait for postgres to be started, not for ready
        volumes:
          - ./persist/home:/opt/snownode/data
        environment:
          # Add your environment settings here
          - SNOWNODE_PG_HOST=database
          - SNOWNODE_PG_DB=snownode?gssEncMode=disable
          - SNOWNODE_PG_USER=idalko
          - SNOWNODE_PG_PWD=idalko
          - SNOWNODE_PORT=9000
    
         #As part of the security improvements, Exalate 5.6.0 validates the origin header
         #that the browser is sending upon every request to Exalate.
         #In order to validate the origin header, Exalate needs to know what is the URL 
         #leading to it.
         #When deploying Exalate to Docker one needs to put an environment variable NODE_SELF_URL.
         #Example:
         # When you deploy Exalate onto a server, you configure a DNS rule such that 
         #whenever people navigate to foo.com, they reach your server's Exalate. 
         #You set up SSL so that https://foo.com leads to your Exalate on your server.
         #Now you need to set environment variable 
    
         - NODE_SELF_URL=https://foo.com 
    
         #for your Exalate docker container.
    
    
        networks:
          - dbnet
          - default
    
    networks:
      dbnet:
        driver: bridge
      default:
        driver: bridge
    
    

    Connecting to Postgres 10 or Higher

    For unencrypted connections from Exalate to a Postgres version 10 or higher, you need to disable gssEncMode with the following setting:

    # exalate is the name of the database on the postgres instance
    #
    SNOWNODE_PG_DB=exalate?gssEncMode=disable

    2. Ensure that a correct database is setup using a createdb.sh

    Create or download a createdb.sh file (referenced from docker-compose.yml):

    Note: Click createdb.sh to download the file.

    The file should contain the following information:

    #!/bin/bash
     
    TEST=`psql -U postgres <<-EOSQL
       SELECT 1 FROM pg_database WHERE datname='$DB_NAME';
    EOSQL`
     
    echo "******CREATING DOCKER DATABASE******"
    if [[ $TEST == "1" ]]; then
        # database exists
        # $? is 0
        exit 0
    else
    psql -U postgres <<-EOSQL
       CREATE ROLE $DB_USER WITH LOGIN ENCRYPTED PASSWORD '${DB_PASS}' SUPERUSER;
    EOSQL
     
    psql -U postgres <<-EOSQL
       CREATE DATABASE $DB_NAME WITH OWNER $DB_USER ENCODING 'UNICODE' LC_COLLATE 'C' LC_CTYPE 'C' TEMPLATE template0;
    EOSQL
     
    psql -U postgres <<-EOSQL
       GRANT ALL PRIVILEGES ON DATABASE $DB_NAME TO $DB_USER;
    EOSQL
    fi
     
    echo ""
    echo "******DOCKER DATABASE CREATED******"
    
    

    Ensure that the volumes are included in your backup strategy:

    • persist

    3. Set Environment Variables if necessary

    Below, you can find the environment variables used for the app container. All of them are optional, and in the given example, we've overridden snownode_PG_DB, snownode_PG_USER, and snownode_PG_PWD just to show how to pass different credentials to the Exalate application.

    Full list of environment variables:
      
    Variable nameExampleDescription
    HTTP_HEADER

    HTTP_HEADERS="TestName1: testAddHeader1"

    Allows additional information to pass between the clients and the server through the request header.
    SNOWNODE_PG_HOSTSNOWNODE_PG_HOST=databaseTells Exalate where is the Postgres database to connect is hosted
    SNOWNODE_PG_DBSNOWNODE_PG_DB=exalateTells Exalate what is the Postgres database name for the Exalate application
    SNOWNODE_PG_USERSNOWNODE_PG_USER=exalateTells the Exalate application what is the Postgres database username for the Exalate application to perform queries with
    SNOWNODE_PG_PWDSNOWNODE_PG_PWD=secretTells the Exalate application what is the Postgres database user's password for the Exalate application to perform queries.
    SNOWNODE_PORTSNOWNODE_PORT=80

    Tells what is the port to start the Exalate application on. Note that this is the port within the exalatesnownode_snownode_1 container, thus if this variable is changed (for example to 80), the

        ports:
          - 9000:9000

    should also be changed to:

        ports:
          - 80:80


    SMTP_HOST_NAMESMTP_HOST_NAME=smtp.gmail.comThe hostname of the SMTP server used to send error notifications
    SMTP_PORTSMTP_PORT=587Port (also check the TLS setting)
    SMTP_FROMSMTP_FROM=my.name@gmail.comEmail that is used to send error notifications
    SMTP_LOGINSMTP_LOGIN=my.nameLogin to the SMTP service
    SMTP_PASSSMTP_PASS=secret

    Password to the SMTP service

    SMTP_TLSSMTP_TLS=trueCan be set to false, but then the snownode_SMTP_PORT should be set to the port, that accepts non-SSL and non-TLS connections
    POLL_PAIR_TIMEPOLL_PAIR_TIME=90 Tells Exalate to set the polling frequency to 90 seconds for PAIR events
    POLL_UPDATE_TIMEPOLL_UPDATE_TIME=90 Tells Exalate to set the polling frequency to 90 seconds for UPDATE events

    Deprecated

    The following fields are not valid anymore starting from version 5.0.28 onward:

    Full list of environment variables
      
    Variable nameExampleDescription
    snownode_SMTP_HOST_NAMEsnownode_SMTP_HOST_NAME=smtp.gmail.comis used to send email notifications about errors blocking synchronization
    snownode_SMTP_PORTsnownode_SMTP_PORT=587is used to send email notifications about errors blocking synchronization
    snownode_SMTP_FROMsnownode_SMTP_FROM=my.name@gmail.comis used to send email notifications about errors blocking synchronization
    snownode_SMTP_USERsnownode_SMTP_USER=my.nameis used to send email notifications about errors blocking synchronization
    snownode_SMTP_PASSsnownode_SMTP_PASS=secretis used to send email notifications about errors blocking synchronization
    snownode_SMTP_TLSsnownode_SMTP_TLS=trueis used to send email notifications about errors blocking synchronization. Can be set to false, but then the snownode_SMTP_PORT should be set to the port, that accepts non-SSL and non-TLS connections

    Using a Proxy for Outgoing Connections

    Whenever Exalate needs to use a proxy to establish outgoing connections, use the following parameters in the environment (naming should be obvious):

    • PROXY_HTTP_HOST
    • PROXY_HTTP_PORT
    • PROXY_HTTPS_HOST
    • PROXY_HTTPS_PORT

    4. Start the Application

    cd ~/exalate-snownode
    docker-compose up -d

    Verify your instance

    After starting Exalate for ServiceNow you need to verify your instance. For more information on how to verify your Exalate for ServiceNow, please this article.

    How to Manage the Application on Docker

    Run Queries to the Application's Database

    cd ~/exalate-snownode
    docker exec -it exalatesnowdnode_database_1 bash
    su postgres
    psql -A $DB_NAME

    You can find all tables using PSQLs \dt+ command:

    \dt+

    All the Postgres SQL queries are permitted

    To exit the application's DB:

    \q
    # \q exits the psql 
    exit
    # exits the postgres user session
    exit
    # exits the exalatesnownode_database_1 bash session

    Inspect the Application's Filesystem

    cd ~/exalate-snownode
    docker exec -it exalatesnownode_snownode_1 bash

    Remove the Application

    cd ~/exalate-snownode
    docker-compose rm

    Remove the Application Data

    Warning:  Do this only if you wish to delete all the synchronization information, including the current synchronizations enqueued to be performed, and synchronization status. Ensure that the remote side you Exalate issues with knows that you're stopping synchronization and are ready to handle synchronization errors.

    cd ~/exalate-snownode
    # docker volume ls | grep exalatesnownode_vol |  awk '{ print $2 }' | xargs docker volume rm
    docker volume rm exalatesnownode_voldatabase
    docker volume rm exalatesnownode_volsnownode

    System Administration Tasks

    With the Exalate for Jira Cloud is running on your environment, you are also required to do the mandatory system administration tasks

    • Backup (& restore tests)
    • Disaster recovery procedure
    • Upgrades whenever needed

    Note: Please note that an Exalate version has a lifespan of 2 years. This is to ensure backward compatibility over the whole platform. There are regular new versions deployed which contain bug fixes, security-related improvements, and even new features. Watch the release notes page for any new versions.

    Upgrading Exalate on Docker

    If you need to upgrade Exalate on Docker, here are the steps to follow:

    1. Edit the YAML File:

      Open the docker-compose.yml file in a text editor and modify the image tag for the service you wish to upgrade.

      # use the latest version https://hub.docker.com/r/idalko/snownode
      image: idalko/snownode:latest
      depends_on:
      - database #wait for postgres to be started, not for ready
      

      Replace latest with the latest or desired version tag.

    2. Pull the Latest Image:

      From the directory containing your docker-compose.yml file, pull the latest image.

      docker-compose pull
      
    3. Recreate the Container:

      Using Docker Compose, you can easily recreate the container with the new image.

      docker-compose up -d
      

      The -d flag runs the containers in detached mode. Docker Compose automatically stops the old container and start a new one based on the updated image.

    4. Post-Upgrade Checks:

      After starting the upgraded container, check to make sure everything is running as expected:

    • Log into the Exalate interface and verify that all your configurations, connections are intact.
    • Test out a few synchronizations to make sure they work as expected.
    • Check for any errors in the Docker logs or the Exalate logs.

    Troubleshooting

    Problems during the installation of the Exalate server for Snownode

    If you have problems during the installation of the Exalate app for Servicenow you can find logs describing possible problems inside /tmp.

    The name for the file is generated randomly and automatically by the OS, but you can find the file by the creation date.

    Problems while running the Exalate server for Snownode

    Logs are generated under the directory: /opt/snownode/data/logs.

    Refer to these logs to get more information about possible problems and communicate with our support if you need any assistance.

    Support

    Please read our Support options.