D-Link DWS-3024L User Manual - Page 64

Discovery and Peer Switches, Assigning the IP Address to Switches and Managed APs

Page 64 highlights

D-Link Unified Access System User Manual The AP can learn up to four Unified Switch IP addresses or DNS names through DHCP option 43 in the DHCP response. This discovery method only works if you configure the DHCP option before the AP receives its network information from the DHCP server. For information about how to configure option 43 with the IP address of one or more Unified Switch, see "Setting the Switch Information in the DHCP Option" on page 73. Discovery and Peer Switches When multiple peer switches are present in the network, you can control which switch or switches are allowed to discover a particular AP by the discovery method you use. If you want to make sure that an AP is discovered by one specific switch, use one of the following methods: • Disable L2 Discovery on all switches and configure the IP address of the AP in only one Unified Switch. • Configure the IP address of one Unified Switch in the AP. • Configure the DHCP option 43 with the IP address of only one Unified Switch. An alternative approach is to configure the RADIUS server to return a switch IP address during AP MAC address checking in the AP authentication process. For information about how to configure the RADIUS server to return a switch IP address, see Appendix B, "Configuring the External RADIUS Server" on page 205. If the RADIUS server indicates that the AP is a valid managed AP and returns an IP address of a switch that is not the same as this switch, then the switch sends a "re-link" message to the access point with the IP address of the Unified Switch to which the AP should be talking to. When the AP gets the re-link message it modifies or sets the Unified Switch IP address, breaks the TCP connection with the current switch and starts a new discovery process. You can configure the D-Link Unified Access System so that each AP is allowed to be managed by any of the four switches in a peer group. If the Unified Switch that manages an AP goes down, one of the backup switches takes over the management responsibilities. To use one or more peer switches as a backup for an AP, use one of the following discovery methods: • If the AP and any of the peer switches are in the same L2 broadcast domain, L2 Discovery is enabled, and all the devices use the default VLAN settings, a peer switch will automatically discover the AP if the primary Unified Switch becomes unavailable. • Configure the IP address of the AP in up to four switches. • Connect to the access point CLI and configure the IP address of up to four switches. • Configure the DHCP option 43 with the IP address of up to four switches in a peer group. Assigning the IP Address to Switches and Managed APs D-Link Unified Switches communicate with each other and with D-Link Access Points by using the IP protocol, so each device must have a valid IP address. 64 © 2001- 2008 D-Link Corporation. All Rights Reserved.

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64
© 2001- 2008 D-Link Corporation.
All Rights Reserved.
D-Link Unified Access System User Manual
The AP can learn up to four Unified Switch IP addresses or DNS names through DHCP option
43 in the DHCP response.
This discovery method only works if you configure the DHCP option before the AP receives
its network information from the DHCP server.
For information about how to configure option 43 with the IP address of one or more Unified
Switch, see
“Setting the Switch Information in the DHCP Option”
on page 73.
Discovery and Peer Switches
When multiple peer switches are present in the network, you can control which switch or
switches are allowed to discover a particular AP by the discovery method you use.
If you want to make sure that an AP is discovered by one specific switch, use one of the
following methods:
Disable L2 Discovery on all switches and configure the IP address of the AP in only one
Unified Switch.
Configure the IP address of one Unified Switch in the AP.
Configure the DHCP option 43 with the IP address of only one Unified Switch.
An alternative approach is to configure the RADIUS server to return a switch IP address
during AP MAC address checking in the AP authentication process. For information about
how to configure the RADIUS server to return a switch IP address, see Appendix B,
“Configuring the External RADIUS Server”
on page 205.
If the RADIUS server indicates that the AP is a valid managed AP and returns an IP address of
a switch that is not the same as this switch, then the switch sends a “re-link” message to the
access point with the IP address of the Unified Switch to which the AP should be talking to.
When the AP gets the re-link message it modifies or sets the Unified Switch IP address, breaks
the TCP connection with the current switch and starts a new discovery process.
You can configure the D-Link Unified Access System so that each AP is allowed to be
managed by any of the four switches in a peer group. If the Unified Switch that manages an
AP goes down, one of the backup switches takes over the management responsibilities.
To use one or more peer switches as a backup for an AP, use one of the following discovery
methods:
If the AP and any of the peer switches are in the same L2 broadcast domain, L2 Discovery
is enabled, and all the devices use the default VLAN settings, a peer switch will
automatically discover the AP if the primary Unified Switch becomes unavailable.
Configure the IP address of the AP in up to four switches.
Connect to the access point CLI and configure the IP address of up to four switches.
Configure the DHCP option 43 with the IP address of up to four switches in a peer group.
Assigning the IP Address to Switches and Managed APs
D-Link Unified Switches communicate with each other and with D-Link Access Points by
using the IP protocol, so each device must have a valid IP address.