Network Interfaces section

Networks are being attached to instances via network interfaces. Network interface can be created either in the subnet or in the virtual switch.

Network interface created in subnet:

  • has Private IP-address from subnet’s CIDR block;
  • can be used as gateway at route creation in route tables;
  • is automatically created at creating an instance in a subnet;
  • has the MAC address, automatically assigned by Cloud;
  • can’t be detached or attached.

Network interface created in a virtual switch:

  • has no addressing;
  • can’t be used as gateway at route creation in route tables;
  • is automatically created at creating an instance in a virtual switch;
  • has the MAC address, automatically assigned by Cloud;
  • can be detached from an instance, if it is not primary (first) network device;
  • can be attached to an instance.

Network interface creation

Click Create button to create a network interface.

Choose network and availability zone in the dialog window. If the selected network is a subnet, then the following options for assigning a private IP-address are available:

  • auto assign - automatically assign random IP-address from subnet’s CIDR block;
  • custom address – specified by user, must be from the Subnet’s CIDR block range.

Attaching network interface to an instance

To attach a network interface, select it in the table and click Attach button. In the attach dialog select the required instance and free device index, then click on Attach network interface. The device index is the target index of the network device inside the guest OS.

Attention

Only network interface that was created in a virtual switch can be attached.

Detaching from instance

To detach network interface, select it in the table, click Detach button and confirm the action.

Network interface deletion

To delete a network interface, click More…. In the drop-down list click Delete. Network interface will be deleted after the confirmation.

Attention

Only detached network interface can be deleted.

Changing description of a network interface

To change description of a network interface, select it from the table and click More…*. In the drop-down list click **Change description. Input new description and confirm the action.

Note

Only ASCII symbols are permitted to be used in the description.

Changing network interface’s security groups

To change list of network interface’s security groups, select the network interface in the table and click More…. In the drop-down list click Change security groups. Select required security groups and confirm the action. To select multiple items press Ctrl and LMB.

Attention

This operation is allowed only for the network interface created in a subnet.

Note

If selected Network Interface has disabled source-dest-check parameter and at least one of specified Security Groups is a source in ingress rules of itself or some other Security Groups, then you can’t assign these SGs to this Network Interface.

Changing source-dest-check attribute

This option is enabled for all newly created Network Interfaces by default. When source-dest-check is enabled, every IP packet which goes through this Network Interface must be destined to or sourced from Network Interface’s IP address.

If you need to setup routing or NAT on the instance, you must disable source-dest-check on its Network Interface.

To change source-dest-check attribute, go to “Network Interfaces” page, select Network Interface and choose More… button. In the drop down menu click Source/dest. check and select needed mode.

Note

If a Network Interface is associated with a Security Group, which is a source in ingress rules of itself or some other SecurityGroups, you can’t disable source-dest-check for this Network Interface.

Changing a public address

To associate a Public IP Address with a network interface, select the interface in the table and click More…. In the drop-down list click Change public address. Choose address and confirm the action.

Attention

This operation is allowed only for the network interface created in a subnet. If the button is inactive, dissasociate the address from the network interface first.

To disassociate Elastic IP Address from the network interface, select the network interface in the table and click More…. In the drop-down list click Disassociate address and confirm the action.

Attention

This operation is allowed only for the network interface created in a subnet.