09-28-2020 10:00 AM
10-03-2020 11:00 AM
You can configure the Brocade device to recognize up to four DNS servers. The first entry serves as the primary default address. If a query to the primary address fails to be resolved after three attempts, the next DNS address is queried (also up to three times). This process continues for each defined DNS address until the query is resolved. The order in which the default DNS addresses are polled is the same as the order in which you enter them.
Use the ip dns server-address command to configure DNS servers.
device(config)# ip dns server-address 10.157.22.199 10.96.7.15 10.95.7.25 10.98.7.15
Alternatively, you can configure DNS servers one after the other.
device(config)# ip dns server-address 10.157.22.199 device(config)# ip dns server-address 10.96.7.15 device(config)# ip dns server-address 10.95.7.25 device(config)# ip dns server-address 10.98.7.15
In this example, the first IP address entered becomes the primary DNS address and all others are secondary addresses. Because IP address 10.98.7.15 is the last address listed, it is also the last address consulted to resolve a query.
As for Multiple DNS:
Flexible authentication communicates with the RADIUS server to authenticate a new client or reauthenticate an already authenticated client. The ICX device supports multiple RADIUS servers. If communication with one of the RADIUS servers times out, the others are tried in sequential order. If a response from a RADIUS server is not received within a specified time (by default, 3 seconds), the RADIUS request times out, and the device retries the request up to three times. If no response is received, that RADIUS server is marked as down, and the next available RADIUS server is chosen, until all servers are exhausted, or a response is received.
Marking the RADIUS server as down helps in making the authentication process faster, as only the available servers are contacted. When configured, the servers that are down are periodically contacted to check if they are available, and when they become available, they are marked accordingly.
There are several professional and experimental quality RADIUS servers, and all servers are configured with the usernames and passwords of authenticated users. For MAC authentication, the username and password are the MAC address itself. The ICX device uses the MAC address for both the username and the password in the request sent to the RADIUS server. For 8021.X, the username and password are typically configured as unique IDs, which the clients use when they log into the network. For example, given a MAC address of 00:10:94:00:fe:aa, the user's file on the RADIUS server is configured with the username and password both set to 00:10:94:00:fe:aa. If a user using dot1x has to authenticate from the same device, the user profile may have name, password.
10-10-2020 11:44 AM
10-10-2020 12:11 PM