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What is the IP address for loopback?
127.0.0.1
The most commonly used IP address on the loopback network is 127.0. 0.1 for IPv4 and ::1 for IPv6. The standard domain name for the address is localhost. A network device also includes an internal loopback address (lo0.
What can loopback be used for?
A loopback address has been built into the IP domain system in order to allow for a device to send and receive its own data packets. Loopback addresses can be useful in various kinds of analysis like testing and debugging, or in allowing routers to communicate in specific ways.
What is 127.0 0.1 IP address?
127.0. 0.1 is the loopback Internet protocol (IP) address also referred to as the localhost. The address is used to establish an IP connection to the same machine or computer being used by the end-user. The same convention is defined for computers that support IPv6 addressing using the connotation of ::1.
Can a loopback interface be a public IP?
In Enterprises, a loopback is likely not to be a public IP (at least using IPv4) unless perhaps its an ISP router. To avoid the NAT issue using private IPs from the Internet, if any direct external/Internet access is allowed to the device, you likely can access it using one of its external interfaces that has a public IP.
Is the loopback interface always up in Juniper?
As the loopback address never changes, it is the best way to identify a device in the network. The loopback interface is always up and it is reachable as long as the route to that IP address is available in the IP routing table.
Can a device be removed from the loopback interface?
While any interface address can be used to determine if the device is online, the loopback address is the preferred method. Whereas interfaces might be removed or addresses changed based on network topology changes, the loopback address never changes.
What do you mean by loopback address in VLAN?
Not sure what you mean by a loopback address in a given vlan. Generally you would have a single loopback for a given L3 device and this is used by any dynamic routing protocols like ospf or eigrp as this interface is always in a up/up state . 04-23-2012 09:56 AM