Im trying to do a practice in packet tracer. Im configuring a 1841 Router (but the problem happens in all routers).
When I try to set an IP address with a mask different of the by defect mask for this Class of address (using VLSM), the router said me that the mask is incorrect (Bad mask) and don’t change anything.
I will implement a classless routing protocol (RIPv2).
Here the line of commands:
Router>
Router>enable
Router#config termin
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#int Ser0/0/0
Router(config-if)#ip address 172.16.199.228 255.255.255.252
Bad mask /30 for address 172.16.199.228 <--- HERE
Router(config-if)#
How can I set an IP address with a no by defect mask?
Thanks you!
172.16.199.228 is the network address. You need to use 172.16.199.229 or .230
Output of ipcalc:
Address: 172.16.199.228 10101100.00010000.11000111.111001 00
Netmask: 255.255.255.252 = 30 11111111.11111111.11111111.111111 00
Wildcard: 0.0.0.3 00000000.00000000.00000000.000000 11
=>
Network: 172.16.199.228/30 10101100.00010000.11000111.111001 00
HostMin: 172.16.199.229 10101100.00010000.11000111.111001 01
HostMax: 172.16.199.230 10101100.00010000.11000111.111001 10
Broadcast: 172.16.199.231 10101100.00010000.11000111.111001 11
Hosts/Net: 2 Class B, Private Internet
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