Management Agent (Worker) Installation
To deploy VMs and run applications on VMs that use the CloudCenter platform, you need the Go-based Management Agent (referred to as agent) installed on each VM.
The Worker image provided or shared by Cisco contains the agent pre-installed using the CentOS 6 operating systems for some supported clouds. These worker images save you time as you do not need to explicitly install the agent yourself.
A Worker image becomes fully functional once you deploy the Worker VM to the cloud.
Using Dynamic Bootstrapping
The CloudCenter management agent can be dynamically installed on VMs launched from images that do not have the Management Agent installed. In this case, you do not need to upload the provided or shared image, instead, the CloudCenter platform automatically detects your selected image, verifies if the agent is installed, and installs the agent if it not installed.
Depending on the support provided by Cisco for, you can decide your approach when launching Worker VMs:
Using Cisco Images
A Worker VM refers to an empty base OS image that has the Go-based Management Agent installed. In the CloudCenter context, a Worker VM is also referred to as an Application VM.
Due to licensing issues, a virtual appliance is not available for custom Windows images.
We recommend that you use the Manual Installation Instructions to install custom Windows images.
The CloudCenter platform ships with pre-bootstrapped CentOS6 image for the clouds listed in Virtual Appliance Overview > Per Cloud Region > Pre-Bootstrap Images.
To use Cisco's CentOS 6 worker image for supported clouds listed in Base OS Images, you can use one of two approaches:
Virtual Appliance: Upload the Cisco provided/shared image to the cloud using the Virtual Appliance Process.
Custom Installer:o manually install the CloudCenter worker image .
Containerize OOB Service
If your Application VM image has the Docker engine installed (by default, CentOS 7 images), the following Out-Of-Box (OOB) CloudCenter services are run as containers inside the Application VM:
Manual Installation Instructions
Question: Why is the Agent installed on Worker VM as part of Application deployment?
Answer: An agent is a program or application that runs on a worker VM. This agent is required by the CloudCenter platform to ensure trust-based queue communication (see Enterprise Service Bus (ESB) for additional details). The agent is configured based on settings configured on the CCO.
Question: What are the various ways in which Application VMs (workers) can communicate with the CCO?
Answer: Two ways for the agent to establish communication with the CCO:
Manually Install Bootstrapping Scripts: Manually install the required binaries (referred to as custom images) to bootstrap the Application VM. See Custom Linux Image for additional details.
Dynamic Bootstrapping Injection: Dynamically install the required binaries to bootstrap the Application VM. See Dynamic Bootstrapping for additional details.
Question: How does the agent communicate with the CCO?
Answer: Once the agent is installed, it needs to connect with the message queue to begin communication with the CCO by way of the RabbitMQ IP address that is provided in the the Agent Bundle URL field when you configure the CCO - Configure Wizard Properties.
Question: When is the incoming access to port 1433 used?
Answer: Port 1433 is enabled as part of agent installer process for Windows OS. This firewall rule must be opened depending on your use of out-of-box Services. If your environment requires access to any service listed here, you must open Port 1433. See Other Firewall Rules for additional context.
Question: When is the IIS feature used?
Answer: The CloudCenter platform installs Internet Information Services (IIS) for Windows-specific agent installations. This is an optional file as identified in Install Worker on a Windows Image and your need for this file depends on your deployment.
Question: Which files are created as part of the agent installation process?
Answer: The list of file created as part of the agent installation process differs for Linux and Windows installations. See the Deployment Lifecycle Scripts > Lifecycle Action Script Definition for additional context.
Question: Why is cliqruser permission required to run some scripts?
Answer: By default, key-based authentication is configured using cliqruser permission – this user refers to the OS user in the Application VM (Worker). See the Deployment Lifecycle Scripts > Lifecycle Action Script Definition for script-specific details on when cliqruser permission is required.
Question: Is the authorized_keys file automatically deleted?
Answer: Yes. After a VM launch the CloudCenter platform cleans up the authorized keys specified in the /root/.ssh/authorized_keys file for all OS types (except Ubunu) during the node initialization phase. For Ubuntu OS, the CloudCenter platform removes the authorized_keys from the /home/ubuntu/.ssh/ folder. After removing the authorized_keys file, the agent injects the specified or auto-generated keys associated with a cliqruser. The cliqruser credentials can be used to log into the VM.
If you do not want the authorized_keys file to be automatically deleted, be sure to set the following flag in the worker image:
Question: Why does the agent program retain files in the C:\temp and C:\ directories?
Answer: Some deployment scripts like resumeScript or reboot or restore take effect based on information retained in these directories. These scripts require information from those files to function as designed. Each script, the level at which it is defined, the script download location, the user running the script, and the location from which the script is run in provided in detail in the Deployment Lifecycle Scripts > Lifecycle Action Script Definition section for both Linux and Windows environments.
Question: Do we install 7zip, Putty, Notepad2 on Windows workers?
Answer: The CloudCenter platform installs the ccc-archiver, a proprietary tool to open TAR files.
Question: Do we explicitly configure an Update on workers? If so, then is there a way for the user to change this frequency or time or disable it?
Answer: The CloudCenter platform does not enable auto updates. Go files are installed as part of the agent installer.
Question: How are application services different from the services created by the agent installation process?
Answer: The agent services and application services are independent of each other. T
Agent Services: Specific to the agent installer. When you install the agent, the Agent installer installs some services to help with the installation and maintenance of the management agent. These files include the CliQr Startup Service, Agent Service, and other services mentioned in Question 4 in this section.