[BUG] EXOS sends one RA even when IPv6 RA is disabled

[ipspace]

It looks like EXOS sends one RA even when it's disabled.

15:08:36.868800 IP6 (class 0xc0, flowlabel 0xde3dd, hlim 255, next-header ICMPv6 (58) payload length: 64) fe80::a8c1:abff:fec9:66b0 > fe80::a8c1:abff:fec7:7cf7: [icmp6 sum ok] ICMP6, router advertisement, length 64
	hop limit 64, Flags [managed, other stateful], pref medium, router lifetime 30s, reachable time 0ms, retrans timer 0ms
	  prefix info option (3), length 32 (4): 2001:db8:1:4::/64, Flags [onlink], valid time 120s, pref. time 120s
	    0x0000:  4080 0000 0078 0000 0078 0000 0000 2001
	    0x0010:  0db8 0001 0004 0000 0000 0000 0000
	  mtu option (5), length 8 (1):  1500
	    0x0000:  0000 0000 05dc
	  source link-address option (1), length 8 (1): aa:c1:ab:c9:66:b0
	    0x0000:  aac1 abc9 66b0

That confuses the integration test (the tests pass after the RA information ages out). If there's no obvious solution, I could tweak the integration test to shut down and reenable the interfaces on all attached hosts to flush their caches.

08-ra:

• Test topology
• Test results