BackupManaged DeviceList

UsingDNSDomain Name System. A DNS server functions as a phone book for the intranet and Internet users. It converts human-readable computer host names into IP addresses and IP addresses into host names. It stores several records for a domain name such as an address 'A' record, name server (NS), and mail exchanger (MX) records. The Address 'A' record is the most important record that is stored in a DNS server, because it provides the required IP address for a network peripheral or element.,remote APRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.receives multiple IP addresses in response to a host name lookup. Known as the backupmanaged devicelist,remote APsRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.go through this list to associate with amanaged device。如果primarymanaged deviceis unavailable or does not respond, theremote APRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.continues through the list until it finds an availablemanaged device。This provides redundancy and failover protection.

The remote AP loses the IP address information received through DNS when it terminates and receives the system profile configuration from themanaged device。如果remote AP loses connectivity on the IPsec tunnel to themanaged device,Remote AP fails over from the primarymanaged deviceto the backupmanaged device。For this scenario, add the IP address of the backupmanaged devicein the backup LMS and the IP address of the primarymanaged devicein the LMS field of the ap-system profile. Network connectivity is lost during this time.As described in the sectionAdvanced Configuration Options, you can also configure aremote APRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.to revert back to the primarymanaged devicewhen it becomes available. To complete this scenario, you must also configure theLMSLocal Management Switch. In multi-controller networks, each controller acts as an LMS and terminates user traffic from the APs, processes, and forwards the traffic to the wired network.IP address and the backupLMSLocal Management Switch. In multi-controller networks, each controller acts as an LMS and terminates user traffic from the APs, processes, and forwards the traffic to the wired network.IP address.

For example, assume you have two data centers, data center 1 and data center 2, and each data center has one mastermanaged devicein the DMZ. You can provision theremote APsRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.to use themanaged devicein data center 1 as the primarymanaged device, and themanaged devicein data center 2 as the backupmanaged device。如果remote APRemote APs extend corporate network to the users working from home or at temporary work sites. Remote APs are deplyed at branch office sites and are connected to the central network on a WAN link.loses connectivity to the primary, it will attempt to establish connectivity to the backup. You define theLMSLocal Management Switch. In multi-controller networks, each controller acts as an LMS and terminates user traffic from the APs, processes, and forwards the traffic to the wired network.parameters in the AP system profile.

Figure 1Sample Backup Scenario