Configuring the Appliance
Repeat the following procedure for each appliance in the cluster:
- Fill in the WCCP clustering Deployment Worksheet.
- Navigate to Configuration > Appliance Settings > WCCP page.
- Click Enable to enable WCCP mode on the appliance.
- Select Cluster (Multiple Caches) option.
- Fill in parameters in the Select SD-WAN Cluster section.
- Enter T5 from your worksheet as the Cache 1 IP, T6 as the Cache 2 IP, T2 as the Subnet Mask, and T1 as the Gateway. Click Save. The Configure Service Group section appears.
- In the Service Group Details section, specify the WAN and LAN service groups (T11 and T12 from your worksheet).
- In the Priority field, select 100 (in practice this value is somewhat arbitrary).
- From the Protocol list, select TCP.
- In the DC Algorithm field, select Deterministic or Least Disruptive. “Deterministic” is always safe to use, and should be used if you are using only two appliances, or are using multiple routers. “Least Disruptive” disrupts fewer user sessions on failover when used with clusters of three or more appliances, but has restrictions on its use.
- Set Service Group Pair Status to On.
- If your router is configured to require a password, enter the password in the Service Group Password field. Otherwise, leave the field blank.
- In the Router Communications Details section, enter the IP address of the router (T8 on your worksheet: often identical to T1 as well). This is the IP address of the appliance-facing router interface. If you use multiple routers to communicate with the appliance, list them all here.
- From the Router Forwarding list, select Level 2 or GRE, according to the capabilities of your router. Use Level 2 if you can, and GRE if you must.
- For the Mask Value, enter the value you determined from the WCCP Clustering worksheet. This is a critical value: a poor choice will result in poor load-balancing or none at all.
- Click Create. This creates the WAN and LAN service groups.
- On the Configuration > Optimization Rules > Link Definitions page, change the bandwidth limits on each defined WAN to 95% of the aggregate speed of all your WANs. This prevents the link from being under-utilized when load-balancing is imperfect. If ICA (XenApp/XenDesktop) is the dominant use, set each appliance to (95% of WAN bandwidth)/N, where N is the number of appliances (or twice the number of appliances if they are SD-WAN 4000 or 5000 units), to divide the bandwidth equally among the appliances. This latter method is most appropriate for applications with large numbers of active connections that have relatively low bandwidth requirements.