Does 0.0.0.0/7 represent the same range as 1.0.0.0/8?

Szymon Marczak asked:

The range of 0.0.0.0/7 is 0.0.0.0 - 1.255.255.255.
The range of 1.0.0.0/8 is 1.0.0.0 - 1.255.255.255.

AFAIK, 0.0.0.0/8 (0.0.0.0 - 0.255.255.255) is not usable. So, do these represent the same range practically?

ip route add 0.0.0.0/7 dev eth1 # 1
ip route add 1.0.0.0/8 dev eth1 # 2

Is the effect the same?

My answer:


Clearly these are not the same.

However, nothing in 0.0.0.0/8 is a valid destination address, so the effect of each route would be the same. Attempts to connect to anything in 0.0.0.0/8 would just fail as always with an Invalid argument error, while attempts to connect to 1.0.0.0/8 would be routed as specified.


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