How to Configure WAN Links for the MCN Site
Mar 14, 2018
The next step is to configure the WAN links for the site.
- Continuing in the site tree for the new MCN site, click the WAN Links branch label.
At this point in a new configuration, there are no WAN links to form a table, and therefore no Open (+) icon to the left of the WAN Links branch. However, if links exist, the + active icon is available. If so, click + to the left of the WAN Links branch to display the table. This also reveals the Add (+), Edit (pencil), Delete (trashcan), and Help (?) active icons to the right of the WAN Links branch.
This reveals the Add (+) and Help (?) active icons to the right of the WAN Links label.
2. Click + to the right of the WAN Links branch to add a new WAN link.
This opens the Add WAN Link dialog box.
3. (Optional) Enter a name for the WAN Link if you do not want to use the default.
The default is the site name, appended with the following suffix:
Where <number> is the number of WAN Links for this site, incremented by one.
4. Select the Access Type from the drop-down menu.
The options are Public Internet, Private Intranet, or Private MPLS.
5. Click Add.
This displays the WAN Links table, adds the new unconfigured link to the table, and opens the Basic Settings configuration form for the link.
Auto Learn of bandwidth consumption
Auto learn runs on system startup and repeats every 5 minutes until a successful result is observed. Auto learn also runs after any WAN link configuration changes are made from the config editor.
You can execute tests manually or schedule tests in the SD-WAN GUI. Results from these tests should also apply to the permitted rate when the test is successful and auto learn is enabled.
When using auto learn on large networks, if config change restarts then all sites run tests simultaneously on the MCN, causing high bandwidth usage leading to inaccurate results. It is recommended that you sechdule bandwidth tests once or twice a day, typically when traffic volume is low.
6. Enter the link details for the new WAN link.
Some guidelines are as follows:
- Some Internet links might be asymmetrical.
- Misconfiguring the permitted speed can adversely affect performance for that link.
- Avoid using burst speeds that surpass the Committed Rate.
- For Internet WAN links, be sure to add the Public IP Address.
7. Click the grey Advanced Settings section bar. This opens the Advanced Settings form for the link.
8. Enter the Advanced Settings for the link.
Enter the following:
- Provider ID – (Optional) Enter a unique ID number from 1-100 to designate WAN Links connected to the same service provider. Virtual WAN uses the Provider ID to differentiate paths when sending duplicate packets.
- Frame Cost (bytes) – Enter the size (in bytes) of the header/trailer added to each packet; for example, the size in bytes of added Ethernet IPG or AAL5 trailers.
- Congestion Threshold – Enter the congestion threshold (in microseconds) after which the WAN link will throttle packet transmission to avoid further congestion.
- MTU Size (bytes) – Enter the largest raw packet size (in bytes), not including the Frame Cost.
9. Click the grey Eligibility section bar. This opens the Eligibility settings form for the link.
10. Select the Eligibility settings for the link.
11. Click the grey Metered Link section bar. This opens the Metered Link settings form for the link.
12. (Optional) Select Enable Metering to enable metering for this link. This displays the Enable Metering settings fields.
13. Configure the metering settings for the link.
Enter the following:
- Data Cap (MB) – Enter the data cap allocation for the link, in megabytes.
- Billing Cycle – Select either Monthly or Weekly from the drop-down menu.
- Starting From – Enter the start date of the billing cycle.
- Set Last Resort – Select this to enable this link as a link of last resort in the event of a failure of all other available links. Under normal WAN conditions, Virtual WAN sends only minimal traffic over metered links, for the purpose of checking link status. However, in the event of a failure, SD-WAN can use active metered links as a last resort for forwarding production traffic.
14. Click Apply. This applies your specified settings to the new WAN link.
The next step is to configure the Access Interfaces for the new WAN link. An Access Interface consists of a Virtual Interface, WAN endpoint IP Address, Gateway IP Address, and Virtual Path Mode defined collectively as an interface for a specific WAN link. Each WAN link must have at least one Access Interface.
15. Click Access Interfaces. This opens the Access Interfaces table for the site.
16. Enter the Access Interfaces settings for the link.
Each WAN link must have at least one Access Interface.
Enter the following:
- Name – This is the name by which this Access Interface will be referenced. Enter a name for the new Access Interface, or accept the default. The default uses the following naming convention:
Where WAN_link_name is the name of the WAN link you are associating with this interface, and number is the number of Access Interfaces currently configured for this link, incremented by 1.
If the name appears truncated, you can place your cursor in the field, then click and hold and roll your mouse right or left to see the truncated portion.
- Virtual Interface – This is the Virtual Interface this Access Interface will use. Select an entry from the drop-down menu of Virtual Interfaces configured for this branch site.
- IP Address – This is the IP Address for the Access Interface endpoint from the appliance to the WAN.
- Gateway IP Address – This is the IP Address for the gateway router.
- Virtual Path Mode – This specifies the priority for Virtual Path traffic on this WAN link. The options are: Primary, Secondary, or Exclude. If set to Exclude, this Access Interface will be used for Internet and Intranet traffic, only.
- Proxy ARP – Select the checkbox to enable. If enabled, the Virtual WAN Appliance replies to ARP requests for the Gateway IP Address, when the gateway is unreachable.
17. Click Apply. This applies your settings and adds the new Access Interface entry to the Access Interfaces table.
You have now finished configuring the new WAN link. Repeat these steps to add and configure additional WAN links for the site.
The next step is to add and configure the routes for the site.