Getting Started | HCLTech

Getting Started

Informix is offered as an hourly Amazon Machine Image (AMI). An AMI is an image applied to compute and memory resources which Amazon calls “EC2”. More details about EC2 can be found here. To place an order in your AWS account, navigate to “Services”, and then “EC2”. Click the “Launch Instance” button.

  • The first step is choosing an AMI. Navigate to “AWS Marketplace” and search for “Informix”. Select “Informix” and proceed through the remaining steps. This will create a new virtual machine in around one minute.
  • Step two, connect to the machine using an ssh program, providing the private key for the keypair specified during order.
  • Next, SSH as the user “ubuntu”. Here’s an example:
    • $ ssh -i ~/.ssh/my_aws_private_key ubuntu@hostname-of-my-informix-ec2
  • After you are logged into the machine, use the sudo command to become the Informix user. For example:
    • $ sudo -u informix bash

As the Informix user, you will be able to run the various Informix commands, such as onstat, onmode, and oninit. The machine is configured with the Informix server running and listening for these types of clients on these ports:


Without TLS

With TLS













InformixHQ Server HTTP




In order to control network traffic to and from the EC2 instance it is preferable to use the Amazon “Security Group” instead of for example an OS-based firewall. Learn more about Security Groups here.

For security reasons the OS accounts on the AMI do not have a password and the only account initially configured for inbound SSH is “centos”. In order to allow a remote client to connect to the Informix database server you can set a password on the desired OS account or create a database user via the CREATE USER statement.

The Informix AMI can be ordered in all AWS regions and on all EC2 types. Since EC2 types have varying amounts of CPU and memory, various types and amounts of storage may be added to an EC2, tuning the Informix Server to meet your needs (E.g. altering the number of CPU VPs, increasing the size of the bufferpool, adding dbspaces on the desired storage devices).

To connect a remote client to Informix, first ensure the AWS Security Group permits traffic on the appropriate ports. To encrypt communication between the client and server, configure the client for TLS by following these guidelines:

The Informix certificate is located at /home/Informix/client_ssl/selfsigned_ssl.cert. For security reasons this certificate should be changed immediately to a certificate you control. Please follow these instructions to configure Informix and these to configure the wire listener.

The web-based monitoring and administration tool, InformixHQ, is also configured and running. The HQ Server and Agent processes run as the OS user "informixhqu". Using a browser connect to InformixHQ at If you desire to access InformixHQ from a remote host first ensure that the AWS Security Group permits the traffic, and then use a browser to connect to https://:8443.

Details about the initial credentials can be found in the /opt/informix/hq/config/ file. This is a text file and can be viewed using e.g. the UNIX “cat” command. See also The password for the InformixHQ server admin can be changed by first logging into InformixHQ as admin and then navigating to the User Settings area. See also