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Link a cluster on a dedicated server to other Selectel products
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Link a cluster on a dedicated server to other Selectel products

A global router is used to set up network connectivity between the dedicated server cluster and other Selectel products.When you create a cluster on a dedicated server, a global router is automatically created.This is a service router that connects the dedicated server and the cloud platform resources required for the Managed Kubernetes cluster to function.

The process of setting up network connectivity depends on whether you are using other global routers:

You can see the list of routers in the control panel: in the top menu, click Products and select Global Router.The service global router is called <cluster_name>-l3vpn, where <cluster_name> is the cluster name.

Link products using a service global router

  1. Connect networks and subnets to the global router to each VLAN and project whose products and services are to be aggregated. For VMware-based cloud you can add networks and subnets only through technical support.
  2. Write routes on the devices.

1. Connect networks and subnets to the global router

Use for a dedicated or hosted server.

You can connect a new network to the router or an existing network if it is not already connected to any of the account's global routers.

  1. In the Control Panel, on the top menu, click Products and select Global Router.

  2. Open the router page → Networks tab. The service global router is named <cluster_name>-l3vpn, where <cluster_name> is the cluster name.

  3. Click Create Network.

  4. Enter a network name, this will only be used in the control panel.

  5. Select the Dedicated Servers product.

  6. Select a pool.

  7. Select VLAN. If you want to create a network up to the internal segment (Q-in-Q), specify its tag, a number from 2 to 4094. If there is already a network up to the VLAN, be sure to specify the Q-in-Q segment of this VLAN.

  8. Enter the subnet name — this will only be used in the control panel.

  9. Enter the CIDR — IP address and private subnet mask. You can enter a new subnet or an existing private subnet of the server if it is not already added to any of the global routers in the account. The subnet must meet the conditions:

    • belong to the RFC 1918 private address range: 10.0.0.0.0/8, 172.16.0.0.0/12, or 192.168.0.0.0/16;
    • do not overlap with the ranges 10.250.0.0.0/16, 10.10.0.0.0/16, and 10.96.0.0/12. These subnets participate in the internal addressing of Managed Kubernetes, their use may cause conflicts in the global router network;
    • have a size of at least /29, as three addresses will be occupied by Selectel network equipment;
    • Do not overlap with other subnets added to this router: The IP addresses of each subnet on the router must not overlap with the IP addresses of other subnets on the router.
  10. If you specified the Q-in-Q tag, make sure to configure Q-in-Q. When configuring, use the subnet you specified in step 9.

  11. Enter the gateway IP or leave the first address from the subnet assigned by default. Do not assign this address to your devices to avoid disrupting the network.

  12. Enter service IPs or leave the last addresses from the subnet assigned by default. Do not assign these addresses to your devices to avoid disrupting the network.

  13. Click Create Network.

  14. Optional: Check the network topology on the global router. In the control panel, from the top menu, click ProductsGlobal Router → Router Page → Network Map.

2. Prescribe routes on the devices

Write routes from the cluster to all devices on the network and from all devices on the network to the cluster.

  1. Connect to the server.

  2. Open the network configuration file:

    vi /etc/netplan/01-netcfg.yaml
  3. At the end of the data block of the desired network interface, add a route:

    routes:
    - to: <ip_address>/<mask>
    via: <gateway>

    Specify:

    • <ip_address>/<mask> — the subnet to which you want to route, with a mask, e.g. 192.168.0.0/28;
    • <gateway> — gateway for the current server subnet, which is specified on the global router.
  4. If you need to prescribe multiple routes, add them sequentially in the same block, for example:

    routes:
    - to: 192.168.0.0/28
    via: 172.16.0.1
    - to: 192.168.1.0/28
    via: 172.16.0.1
  5. Save the file.

  6. Check the settings:

    sudo netplan try
  7. Apply the changes:

    netplan apply

Link products through global router interconnection

  1. Merge global routers.
  2. Write routes on the devices.

1. Merge global routers

  1. Make sure that the subnets of the routers to be merged do not overlap — the IP addresses of each subnet must not overlap with the IP addresses of other subnets. You can view the list of subnets in the control panel: from the top menu, click ProductsGlobal Router → Router page → Networks tab.
  2. Create a ticket. In the ticket, specify the IDs of the global routers that you want to merge. You can copy the router IDs from the control panel: in the top menu, click ProductsGlobal Router → Router page → copy the ID under the router name.
  3. Wait for a response in the ticket that the global routers have been merged.

2. Prescribe routes on the devices

Write routes from the cluster to all devices on the network and from all devices on the network to the cluster.

  1. Connect to the server.

  2. Open the network configuration file:

    vi /etc/netplan/01-netcfg.yaml
  3. At the end of the data block of the desired network interface, add a route:

    routes:
    - to: <ip_address>/<mask>
    via: <gateway>

    Specify:

    • <ip_address>/<mask> — the subnet to which you want to route, with a mask, e.g. 192.168.0.0/28;
    • <gateway> — gateway for the current server subnet, which is specified on the global router.
  4. If you need to prescribe multiple routes, add them sequentially in the same block, for example:

    routes:
    - to: 192.168.0.0/28
    via: 172.16.0.1
    - to: 192.168.1.0/28
    via: 172.16.0.1
  5. Save the file.

  6. Check the settings:

    sudo netplan try
  7. Apply the changes:

    netplan apply