At 9:42 PM -0600 9/16/98, Kyle D. Smith wrote:
First of all, i know that this is not the best place to ask this quesiton, but it is the only place that can quickly come to mind...
I have a customer who has a block of 62 ip addresses (206.206.162.130 -> 206.206.162.190 and one for network/brodcast). They are current expanding their network, and need around 30 more ip addresses. I went ahead and allocated them the following IP address pool (207.66.81.144 -> 207.66.81.174 with network/brodcast address.) I attempted to use the new address on a Apple Macintosh (PowerMac 6500/75) and it erturned an error message saying that the router was not on the subnet, and that it could not use the new address. I know I should remember how to fix that, but I am not sure what to do.... Any help or guidence would be greatly appreciated. Thank you very much.
For a quick reference, download ftp://ftp.isi.edu/in-notes/rfc1878.txt This will give you some templates for VLSM subnets. Here are some relevant sections: 255.255.255.192 4 nets N.N.N.0 N.N.N.1-62 N.N.N.63 2 bit Class C 62 N.N.N.64 N.N.N.65-126 N.N.N.127 10 bit Class B N.N.N.128 N.N.N.129-190 N.N.N.191 N.N.N.192 N.N.N.193-254 N.N.N.255 255.255.255.224 8 nets N.N.N.0 N.N.N.1-30 N.N.N.31 3 bit Class C 30 N.N.N.32 N.N.N.33-62 N.N.N.63 11 bit Class B N.N.N.64 N.N.N.65-94 N.N.N.95 N.N.N.96 N.N.N.97-126 N.N.N.127 N.N.N.128 N.N.N.129-158 N.N.N.159 N.N.N.160 N.N.N.161-190 N.N.N.191 N.N.N.192 N.N.N.193-222 N.N.N.223 N.N.N.224 N.N.N.225-254 N.N.N.255 As you see, the first block you assigned is fully in the third /26 range. The second block, starting with 144, is off somehow. I am a little unclear if you wanted to give them a /26 or /27 block. In addition, you need to make sure your router interface is visible on both subnets. I'm assuming your configuration is something like this: R1 | | ---------------------------- with the Macs addressed either in 206.206.162.130 or 207.66.81.144 The router interface needs to have an address in both subnets. On Cisco, this is a secondary address, while on Bay, it would be a multinet addresss. Strategically, encourage your customer to use DHCP address assignment. If he does this, you can create a single block on the DHCP server for his future address needs, and the workstations simply need to reboot to get new addresses. As a shameless commercial plug, I have a book on addressing coming out in November from Macmillan.