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Public Cloud Networks

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All virtual machines can be connected to a private network and a public one (the Internet). Internet connectivity can be configured via Edge Routers or Direct Connected subnets.

Public network

You can connect virtual machines to the public network (the Internet) using one of the following schemes:

  • via a local Edge Router (default). Virtual machines in a virtual data center communicate via a private network that connects to an Edge Router, and the Edge Router connects to the Internet. Firewall and NAT must be configured on the Edge Router;
  • via a Direct Connected subnet, which connects virtual machines and links them to the public network without using a router. You must configure the Firewall on each virtual machine.

Connection via Edge Router

An Edge Router is a software router used by virtual machines to access the public network. Virtual machines communicate with the Edge Router via a private network.

When a virtual data center is created, an Edge Router of Compact size is automatically created with a preconfigured private network default_net and basic Firewall and NAT rules, for more details see the Edge Routers guide.

You can create a new Edge Router and add a private network to it. After that, you must configure the Firewall and NAT rules for SSH/RDP access. Additionally, you can configure a VPN and load balancing.

Connection via Direct Connected subnet

A Direct Connected subnet is a public subnet created at the virtual data center level, to which virtual machines connect directly to receive IP addresses from this network without using an additional router (Edge Router) and without needing to configure Firewall and NAT. If the VMware Tools utility (the open-vm-tools package) is installed inside the virtual machine and on the network interface, the IP address will be added automatically during virtual machine provisioning.

A Direct Connected subnet can contain between 5 and 253 IPv4 addresses. The limit for Direct Connected subnets is five per organization. To increase the limit, create a ticket.

For more information on working with Direct Connected subnets, see the Managing Direct Connected subnets guide.

Private network

A network can be available within a virtual data center or a group of them and can be one of the following types:

  • Routed — a private network connecting virtual machines in a virtual data center to an Edge Router. It is accessible from the Internet if NAT rules are configured. When a virtual data center is created, a preconfigured default_net network of the Routed type is created automatically;
  • Isolated — a private network connecting virtual machines that is available only within a virtual data center and is not accessible from the Internet. Such a network can be made shared between virtual data centers within an organization, for more details see the Creating a shared network between virtual data centers guide.

Preconfigured private network default_net

The preconfigured default_net private network is created automatically after a virtual data center and a default (Compact size) Edge Router are created. You can use it to connect a virtual machine to the Internet.

default_net network specifications:

  • static IP pool: 10.0.0.101 — 10.0.0.132;
  • DNS: Primary DNS 188.93.16.19 and Secondary DNS 188.93.17.19;
  • the network has Internet access: it is connected to an Edge Router with configured NAT and Firewall rules;
  • a DHCP server with an IP pool of 10.0.0.2 — 10.0.0.100 is running on the network Edge Router.

Blocked ports

To protect Selectel infrastructure from malicious network activity, we have blocked certain ports, including port 25 (mail newsletters).

If a port is not covered by the listed restrictions, check its availability from the OS using the Nmap utility.