FYI: usage of fe80:: address needs interface name in URL (Linux)

[sander]

I just found this out:

http://[fe80::218:deff:fe10:c06%wlan0]:8080/sabnzbd/ is a working URL.

http://[fe80::218:deff:fe10:c06]:8080/sabnzbd/ does not work: it results in an empty, white page.

My conclusion: when using a local fe80:: interface, you need to specify the local interface via which to reach that fe80 address in the URL. In this case: %wlan0

This is how it works on Linux. I don't know about other OSes.

[shypike]

Do you have multiple network interfaces?
It looks like the %wlan0 part is a binding spec to pick the right card.

[sander]

Do you have multiple network interfaces?

My laptop has. My desktop hasn't (just eth0 and loopback). And even my desktop needs the interface-indicator. Even for it's own FE80-address.

It looks like the %wlan0 part is a binding spec to pick the right card.

Exactly. It's a kind of mini-routing in the FE80-address: 'use address via this interface'. Apparently the OS is too 'lazy' to search it's own interfaces.
There is a situation where I can understand this: multiple LAN-interfaces (for example wired and wifi) on a machine, all with FE80 addresses, where you want to reach another computer on it's FE80-address. In that case I do understand you must specify via which interface that FE80 address must be approached; a FE80 address could be anywhere.

So, it's my conclusion FE80 addresses are not an easy solution for LAN access. Until now I thought FE80 was easier than self-changing DHCP-assigned IPv4 addresses.
But, I could be wrong: I would like to know what's experienced on other OSes (Mac and Windows).