I thought that the loopback IP address of my machine is 127.0.0.1
.
I do not understand why am I able to ping IP addresses until 127.255.255.254
.
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Sign up to join this communityThe entire address block 127.0.0.0/8
is the block of loopback addresses for a host. There are RFCs that explain this.
The goes back at least as far as RFC 990, ASSIGNED NUMBERS:
The class A network number 127 is assigned the "loopback" function, that is, a datagram sent by a higher level protocol to a network 127 address should loop back inside the host. No datagram "sent" to a network 127 address should ever appear on any network anywhere.
RFC 1122, Requirements for Internet Hosts -- Communication Layers:
(g) { 127, }
Internal host loopback address. Addresses of this form MUST NOT appear outside a host.
Also RFC 3330, Special-Use IPv4 Addresses:
127.0.0.0/8 - This block is assigned for use as the Internet host loopback address. A datagram sent by a higher level protocol to an address anywhere within this block should loop back inside the host. This is ordinarily implemented using only 127.0.0.1/32 for loopback, but no addresses within this block should ever appear on any network anywhere [RFC1700, page 5].
localhost
resolves to 127.0.0.1 which is the most commonly used IPv4 loopback address. – Hung Tran Oct 2 '17 at 8:08loopback IP addresses
, NOT local. – Hung Tran Oct 2 '17 at 9:11