Jelastic Hardware Requirements: General Concepts

Commonly, the Jelastic cluster structure can be shown as below:

It consists of:
  • infrastructure hardware nodes (infra nodes) - servers with Jelastic services running
  • user hardware nodes (user nodes) - servers with user applications
  • external network, which usually should be accessible from Internet, with one or more ranges of public IP addresses, routable in this network
  • isolated internal network, fully devoted to Jelastic cluster, with private IP addresses
  • DNS zone, which will be controlled by Jelastic (i.e. elastic-platform.com)
  • wildcard SSL certificate for this domain (i.e. covering also *.elastic-platform.com)

Note: Whilst choosing the hardware provider, please, consider the HW/VM Vendors Limitations.

High-Level Requirements

According to the general concepts, to have a Jelastic platform installed, you need to provide:

1. Bare-metal servers or virtual machines - hardware nodes. The hardware requirements depend on a particular installation scenario

2. External network, which usually should be accessible for platform users (customers/visitors)
  • one or more public IP ranges, routable in this network

3. Internal network, isolated for Jelastic use only
  • one or more private IP ranges, routable in this network
  • a single network of /8 or /16 addresses is preferred

4. DNS sub-domain, which will be controlled by Jelastic:
  • *.infra-domain.hosterdomain.com
  • *.user-domain.hosterdomain.com
  • you will have to configure the proper DNS delegation from the parent DNS domain (i.e. hosterdomain.com) to these DNS sub-domains 

5. Multidomain Wildcard SSL certificate for this DNS subdomain, covering the following DNS names:
  • *.infra-domain.hosterdomain.com (added as SAN)
  • *.cs.infra-domain.hosterdomain.com (added as SAN)
  • *.user-domain.hosterdomain.com (added as CN)

6. Storage for the user-uploaded content (Uploader Storage), can be shared with Docker templates cache storage
  • external NFS mount or SCSI lun, shared over infrastructure nodes, is recommended

7. Storage for Docker templates cache (Docker Storage), can be shared with uploader storage
  • external NFS mount or SCSI lun, shared over infrastructure nodes, is recommended

Installation Scenarios

For the public beta and commercial launch, there are two possible scenarios of the Jelastic Platform installation:

Please refer to the appropriate linked page to see the specific scenario-depended requirements on hardware, network and OS configurations.

In case of following the latter scenario, the next additional high-level requirements are added:
  • Parallels Cloud Storage cluster components installed
  • Internal network, dedicated to the Parallels Cloud Storage
    • 2 or more NICs per server for PCStorage might be required (please see the sizing guidelines within the document, linked above)

System Settings

The following OS settings are configured on the servers during the Jelastic PaaS Installation. They must not be changed or removed after the installation. Please, review the list below for possible contradictions with your operations and maintenance practices and contact Jelastic Support or Operations in case any of them represents a potential conflict:

  • Changes to the system configuration files, listed in the Configuration Files article, are prohibited.
  • Jelastic PaaS installation updates additional system configuration files, listed in the Configuration Files article; these changes must not be removed or overwritten after the installation.
  • Certain kernel modules, listed in the Kernel Modules article, are configured for pre-loading during the Jelastic PaaS installation and these settings must not be altered after the installation.
  • TCP stack settings are modified during the Jelastic PaaS installation and must not be altered after the installation.
  • The Jelastic PaaS installation adds certain iptables rules, as described in the iptables Rules article, and those rules must not be removed or overwritten after the installation.
  • The list of IP addresses, used by Jelastic infrastructure, should be allowed by your firewall.
  • For the Jelastic Operations Team to have the ability to access the required hardware node in case of emergency, the appropriate SSH keys should be added to each of them.
  • Server timezone is set to UTC during the Jelastic PaaS installation, and must not be updated after the installation.
  • SELinux module is switched OFF during the Jelastic PaaS installation and must not be turned ON after the installation.

For more details on maintaining Jelastic PaaS, please, refer to the Jelastic Operations Guide.