JunOS version: 12.3R11.2

Juniper EX switch with 2 VLANs:
vlan 0: IPv4:
This vlan is used for private IP space

vlan 1: IPv4: X.X.X.254/24
IPv6: XXXX:XXXX:X:XXX::ffff/64
This vlan is used for public IP space

Devices connected to the switch can ping the gateway of my assigned IPv6 block (XXXX:XXXX:X:XXX::1), they can ping each other, and they can ping the XXXX:XXXX:X:XXX::ffff address assigned to the public vlan however they can't ping anything outside the LAN (ex. Google 2001:4860:4860::8888). IPv4 works fine.

There is a static route for next-hop but that is the only static route configured. Do I need to add a static route for ::/0 too? What would be the next-hop?

Any help is appreciated - I am learning this as I go.

EDIT: additional info

pings gateway okay
user@host:RE:0% ping6 xxxx:xxxx:x:xxx::1
PING6(56=40+8+8 bytes) xxxx:xxxx:x:xxx::ffff --> xxxx:xxxx:x:xxx::1
16 bytes from xxxx:xxxx:x:xxx::1, icmp_seq=0 hlim=64 time=6.213 ms
16 bytes from xxxx:xxxx:x:xxx::1, icmp_seq=1 hlim=64 time=6.516 ms
16 bytes from xxxx:xxxx:x:xxx::1, icmp_seq=2 hlim=64 time=1.684 ms
16 bytes from xxxx:xxxx:x:xxx::1, icmp_seq=3 hlim=64 time=1.720 ms

fails outside LAN
user@host:RE:0% ping6 2001:4860:4860::8888
PING6(56=40+8+8 bytes) xxxx:xxxx:x:xxx::ffff --> 2001:4860:4860::8888
ping6: sendmsg: No route to host
ping6: wrote 2001:4860:4860::8888 16 chars, ret=-1
ping6: sendmsg: No route to host
ping6: wrote 2001:4860:4860::8888 16 chars, ret=-1
ping6: sendmsg: No route to host
ping6: wrote 2001:4860:4860::8888 16 chars, ret=-1

  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
    – Ron Maupin
    Aug 14, 2017 at 21:30

1 Answer 1


IPv6, like IPv4, routing needs to have a route to the destination, even if it is only a default route, otherwise the traffic gets dropped by the router.

Routing works the same for any IP version: the router looks at the destination IP address, and it tries to find a match in its routing table. Absent such a match, the traffic is dropped.

You either need a default route from your ISP, or you need to manually configure a route to ::/0 with a next hop as your ISP's IPv6 interface.


Normally, your ISP should assign you a /48 for your site, and you should set up IPv6 prefix delegation to assign your individual networks on your LAN. Some ISPs will only assign a /56, or, more rarely, a /60. The ISPs will not advertise any prefix longer than a /48, so that the addresses will belong to your ISP, but you can easily get a /48 from your RIR. If you get provider-independent addressing from your RIR, you may need to use BGP with your ISP, or negotiate for the ISP to advertise your IPv6 network.

  • I was only assigned a /64 from my ISP. I added a static route for ::/0 next-hop xxxx:xxxx:x:xxx::1 which should be correct as xxxx:xxxx:x:xxx::1 is my ISPs gateway. Now a ping outside the LAN does not show the "no route to host" message but it still fails. Oct 4, 2016 at 3:46
  • If you only have one /64, that is only enough for your link to the ISP, with nothing for your LAN. Are you sure your ISP isn't delegating a smaller prefix to you? IANA recommends giving every customer site a maximum prefix length of /48, but many ISPs objected, and now delegate /56 prefixes. If your ISP is flouting IANA, you can easily get a provider independent /48 from your RIR. You will need to work with your ISP to advertise it.
    – Ron Maupin
    Oct 4, 2016 at 3:50

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