### Cisco ###

	Cisco#show running-config interface lo10
	Building configuration...

	Current configuration : 77 bytes
	!
	interface Loopback10
	 no ip address
	 ipv6 address 2001:67C:208C::1/12             <<<<!!!==== tried to type /128
	end

	Cisco#show ipv6 route
	IPv6 Routing Table - default - 3 entries
	Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
	       B - BGP, HA - Home Agent, MR - Mobile Router, R - RIP
	       H - NHRP, I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea
	       IS - ISIS summary, D - EIGRP, EX - EIGRP external, NM - NEMO
	       ND - ND Default, NDp - ND Prefix, DCE - Destination, NDr - Redirect
	       O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
	       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2, la - LISP alt
	       lr - LISP site-registrations, ld - LISP dyn-eid, a - Application
	C   2000::/12 [0/0]                            <<<<!!!==== WHELP ====
	     via Loopback10, directly connected
	L   2001:67C:208C::1/128 [0/0]
	     via Loopback10, receive
	L   FF00::/8 [0/0]
	     via Null0, receive
	IOU5#

### Juniper ###

	lab@juniper> show configuration interfaces lo0    
	unit 0 {
	    family inet6 {
		address 2001:67c:208c::1/12;          <<<<!!!==== operator forgot to enter trailing 8
	    }
	}

	lab@juniper> show route table inet6.0 

	inet6.0: 6 destinations, 6 routes (6 active, 0 holddown, 0 hidden)
	+ = Active Route, - = Last Active, * = Both

	2000::/12          *[Direct/0] 00:01:49       <<<<!!!==== WHELP ====
			    >  via lo0.0
	2001:67c:208c::1/128
			   *[Local/0] 00:01:49
			       Local via lo0.0
	2001:db8::/128     *[Local/0] 68w0d 18:03:19
			       Reject
	fe80::5e5e:ab00:3d7:b203/128
			   *[Local/0] 68w0d 18:03:19
			       Reject
	fe80::5e5e:ab0f:fcd7:b2ff/128
			   *[Direct/0] 00:01:49
			    >  via lo0.0
	ff02::2/128        *[INET6/0] 68w0d 18:04:39
			       MultiRecv

	lab@juniper>