pppoe1: flags=88d1<UP,POINTOPOINT,RUNNING,NOARP,SIMPLEX,MULTICAST> metric 0 mtu 1484 inet6 fe80::290:bff:fe6d:aa96%pppoe1 prefixlen 64 scopeid 0x16 inet6 fe80::290:bff:fe6d:aa92%pppoe1 prefixlen 64 scopeid 0x16 inet xx.xx.xx.xx --> xx.xx.xx.xx netmask 0xffffffff nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>root@fw:~ # ifconfig pppoe1 inet6 xx:xx:xx:xx::1 prefixlen 64 aliasifconfig: ioctl (SIOCAIFADDR): File exists
"File exists" would indicate it works ...
... but it's not displayed by the OS.