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Question
How Do I Determine the Automatic IP Address of My LXI Device?
Solution Auto IP is a mechanism for finding an unused IP address in the range 169.254.X.Y, where X is in the range 1 through 254 and Y is in the range 0 through 255. The device will first attempt to obtain the specific address 169.254.X.Y, where X and Y are the second-to-last and last octets (bytes) of the device’s MAC address. However, X will be set to 1 if it is 0 in the MAC address, and to 254 if it is 255 in the MAC address. This is in accordance with the Auto IP standard (RFC 3927). If this address is already in use, the unit will attempt to obtain other IP addresses in a pseudorandom fashion until it finds one that is available.

To illustrate the Auto IP mechanism, the following table lists the Auto IP default address for some example MAC addresses.

MAC Address IP Address
00:0D:3F:01:00:01 169.254.1.1
00:0D:3F:01:01:01 169.254.1.1
00:0D:3F:01:A3:28 169.254.163.40
00:0D:3F:01:FE:FE 169.254.254.254
00:0D:3F:01:FF:FE 169.254.254.254

If this strategy does not work for successfully work for determining the auto IP address of an LXI device, see the knowledge base entry for resetting the LAN settings on the device.