IPv6 NoPrefixAvail

[igorizyumin]

I just got Sonic a couple of weeks ago. It's been working great. However, I recently swapped out my router with a newer, faster one, and now I cannot seem to get an IPv6 prefix. It's been roughly 48 hours thus far, so I think it should have been long enough for any existing leases to time out. I tried a couple of things, including changing the DUID and adding and removing various DHCP client options, with no change.

The router is running openwrt with odhcp6c as the client.

I did notice that if I configure the client to request an NA, I get a single /128 address, but I cannot seem to get a PD. For reference, the router was requesting both the NA and the PD in a single Solicit message.

Tcpdump on the router shows the following:

22:59:07.308572 IP6 (flowlabel 0x91dbf, hlim 1, next-header UDP (17) payload length: 105) fe80::9683:c4ff:fea8:a822.546 > ff02::1:2.547: [bad udp cksum 0x0050 -> 0xeba3!] dhcp6 solicit (xid=cacdfa (elapsed-time 762) (option-request SIP-servers-domain SIP-servers-address DNS-server DNS-search-list SNTP-servers NTP-server AFTR-Name opt_67 opt_94 opt_95 opt_96 opt_82) (client-ID hwaddr type 1 9483c4a8a822) (IA_PD IAID:1 T1:0 T2:0 (IA_PD-prefix ::/56 pltime:0 vltime:0)))

22:59:11.885247 IP6 (class 0xc0, hlim 64, next-header UDP (17) payload length: 173) fe80::e65dfe89:77f4.547 > fe80::9683:c4ff:fea8:a822.546: [udp sum ok] dhcp6 advertise (xid=cacdfa (client-ID hwaddr type 1 9483c4a8a822) (server-ID vid 0000058365343a35) (IA_PD IAID:1 T1:0 T2:0 (IA_PD-prefix ::/128 pltime:0 vltime:0 (status-code NoPrefixAvail))) (DNS-server 2001:5a8::11 2001:5a8::33))

[igorizyumin]

Looks like it started working by itself... Must be a really long timeout on the lease or something.

[gadams]

Unfortunately, I am now experiencing NoPrefixAvail from the Sonic DHCPv6 server as well. In my case, it began immediately after a scheduled emergency maintenance a day and a half ago. The link didn't go down, but during the maintenance window, DHCPv4 and DHCPv6 responses ceased, and when they came back, I am able to get an IA_NA response, but no successful IA_PD (prefix delegation). Like you, I get NoPrefixAvail:

Code: Select all

11:32:36.320584 IP6 (flowlabel 0xe1350, hlim 1, next-header UDP (17) payload length: 85) fe80::227c:14ff:fef5:9059.dhcpv6-client > ff02::1:2.dhcpv6-server: dhcp6 solicit (xid=884782 (client-ID hwaddr type 1 207c14f59051) (elapsed-time 65535) (option-request DNS-server DNS-search-list) (IA_PD IAID:1 T1:0 T2:0 (IA_PD-prefix ::/56 pltime:4294967295 vltime:4294967295)))

11:32:36.484895 IP6 (class 0xc0, hlim 64, next-header UDP (17) payload length: 144) fe80::b6f9:5dff:fe35:2e3c.dhcpv6-server > fe80::227c:14ff:fef5:9059.dhcpv6-client: [udp sum ok] dhcp6 advertise (xid=884782 (client-ID hwaddr type 1 207c14f59051) (server-ID vid 0000058362343a66) (IA_PD IAID:1 T1:0 T2:0 (status-code NoPrefixAvail)) (DNS-server ns1.sonic.net ns2.sonic.net))

How long in total were you without a prefix? (Although I imagine that may have no bearing on when it returns for me; I don't imagine this is some timeout, but rather a bit of configuration in the new equipment on the Sonic end that's been missed and will need to be rectified.)

[conradpino]

Sonic turned up 10G Fiber service Tuesday afternoon (5 days ago) in Castro Valley. I'm using MikroTik RB5009UG router.

• IPv4 MTU 1500 lease time 6 hours
• IPv6 MTU 1500 lease time 6 hours
• IPv6 Prefix Delegation 2001:5a8:xxxx:xx00::/56
• IPv6 MTU 1500 suggests native IPv6 implementation.
• Hurricane Electric IPv6 Tunnel Broker tunnels are working.