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IPv6 routing/connectivity gone awry today?

MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

IPv6 routing/connectivity gone awry today?

This could well be a problem at my end but I thought I'd raise it in case not... I seem to have lost my IPv6 connectivity. Unfortunately I'm away from home at the moment and don't dare diagnose remotely as it always seems to end up with me disabling the very interface I'm connected through!
My address/DHCP details:

Cisco837#sh ipv6 int brief
FastEthernet1              [up/up]
FastEthernet2              [down/down]
FastEthernet3              [down/down]
FastEthernet4              [down/down]
Ethernet0                  [up/up]
    FE80::212:D9FF:FED8:EE2B
    2A02:16C8:2000:6000:212:D9FF:FED8:EE2B
ATM0                      [up/up]
Ethernet2                  [administratively down/down]
Tunnel0                    [administratively down/down]
    FE80::51AE:8B49
    2001:470:1F08:1917::2
Dialer1                    [up/up]
    FE80::212:D9FF:FED8:EE2B
NVI0                      [up/up]
Virtual-Access1            [up/up]
Virtual-Access2            [up/up]
Cisco837#sh ipv6 dhcp int
Ethernet0 is in server mode
  Using pool: IPV6DHCP
  Preference value: 0
  Hint from client: ignored
  Rapid-Commit: disabled
Dialer1 is in client mode
  State is OPEN
  Renew will be sent in 7w0d
  List of known servers:
    Reachable via address: FE80::90:1A00:3A3:AB15
    DUID: 000200000A4C453332302F373435414333334558322F03
    Preference: 0
    Configuration parameters:
      IA PD: IA ID 0x000D0001, T1 INFINITY, T2 INFINITY
        Prefix: 2A02:16C8:2000:6000::/56
                preferred lifetime INFINITY, valid lifetime INFINITY
      DNS server: 2001:470:20::2
  Prefix name: MYPLUSNETPREFIX
  Rapid-Commit: enabled

I can reach what I assume to be the RADIUS/DHCPv6 server:

Cisco837#ping ipv6 FE80::90:1A00:3A3:AB15
Output Interface: dialer 1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to FE80::90:1A00:3A3:AB15, timeout is 2 seconds:
Packet sent with a source address of FE80::212:D9FF:FED8:EE2B
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/36/44 ms

But I cannot reach any further over IPv6, but can over IPv4:

Cisco837#ping ipv6 targur.newtonnet.co.uk
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:BA8:1F1:F137::2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
Cisco837#ping ip targur.newtonnet.co.uk
Translating "targur.newtonnet.co.uk"...domain server (212.159.13.49) [OK]
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 212.13.195.175, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/36/40 ms

Anyone else having any trouble? As mentioned I'll have to wait until I'm back anyway but it could be useful to know if it's just me.
Mathew
12 REPLIES 12
brueton
Grafter
Posts: 312
Thanks: 7
Registered: ‎03-07-2009

Re: IPv6 routing/connectivity gone awry today?

No problems for me.
PB
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

Thanks Pete. I decided to renew the DHCP lease and it's back working now:

Cisco837#clear ipv6 dhcp client dialer 1
Cisco837#sh ipv6 dhcp int
Ethernet0 is in server mode
  Using pool: IPV6DHCP
  Preference value: 0
  Hint from client: ignored
  Rapid-Commit: disabled
Dialer1 is in client mode
  State is OPEN
  Renew will be sent in 7w0d
  List of known servers:
    Reachable via address: FE80::90:1A00:3A3:AB15
    DUID: 000200000A4C453332302F373435414333334558322F03
    Preference: 0
    Configuration parameters:
      IA PD: IA ID 0x000D0001, T1 INFINITY, T2 INFINITY
        Prefix: 2A02:16C8:2000:6000::/56
                preferred lifetime INFINITY, valid lifetime INFINITY
      DNS server: 2001:470:20::2
  Prefix name: MYPLUSNETPREFIX
  Rapid-Commit: enabled
Cisco837#ping ipv6 targur.newtonnet.co.uk
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:BA8:1F1:F137::2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/36 ms

I think I have read somewhere about a bug (issue?) in IOS that requires a forced DHCPv6 renewal following a reconnect (which I did have overnight) so will have to do some further digging.
Cheers,
Mathew
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

I've found the following which hints at something of a disaster for those using Cisco kit that doesn't support EEM:
http://blog.ioshints.info/2010/10/dhcpv6-over-pppoe-total-disaster.html
Specifically, if/when the link goes down (and comes back up) the DHCPv6 client is blissfully unaware and doesn't renew its lease until the timer runs out... 7 weeks later in this case! EEM, if supported, can be used to detect and force an update.
Time to renew my 837...
Mathew
_CN_
Plusnet Alumni (retired)
Plusnet Alumni (retired)
Posts: 385
Registered: ‎11-06-2007

Re: IPv6 routing/connectivity gone awry today?

should help
event manager applet MONITOR-IPV6-DHCP-APP
event syslog pattern "DIALER-6-BIND"
action 1.0 cli command "enable"
action 1.1 cli command "clear ipv6 dhcp client Dialer1"
action 2.0 syslog priority debugging msg "Refreshed IPv6 DHCP PD lease (Dialer rebind)"
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

Thanks Carl, unfortunately the 837 doesn't support EEM.  Sad
I have however created a workaround - a script to monitor my syslog, detect the Virtual-Interface state change and login to the router to renew the lease. It's hacky[1], but it works. Will post it up later in case it's of use to anyone else.
Mathew
[1] Althought so is having to use EEM - Cisco should sort this issue out!
_CN_
Plusnet Alumni (retired)
Plusnet Alumni (retired)
Posts: 385
Registered: ‎11-06-2007

Re: IPv6 routing/connectivity gone awry today?

cool, thanks for the update Mathew.  Can't wait to have a go on the Cat Feeder lol
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

I may need to get you to test it prior to the 'big day' if that's alright!
My main issue has been one of video streaming - even running at a leisurely 2fps I require 150kbps upload, and my intention is to have two cameras running so that means I can support all of around 1-and-a-half concurrent users at any one time!
Of course, this could actually turn out to be more than enough but just in case it does attract some interest I've taken to streaming all the video to a well connected offsite server and will echo it to connecting users from there. Trouble is this just makes an already complicated even more so so we'll have to see how it pans out!
Your native IPv6 connectivity is however a real bonus over my previous tunneling so thank you for that.
Mathew
dave
Plusnet Staff
Plusnet Staff
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Registered: ‎04-04-2007

Re: IPv6 routing/connectivity gone awry today?

Matthew I'll sort you out some faster upload tomorrow (Max Premium/Annex M depending on which network you're on).
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

Wow, thanks Dave. To be honest I'm a bit new to ADSL (brought up on nowt but cable!) and didn't even realise there were different upload rates available. I'm on MaxDSL by the way.
Incidentally, I did try out a Cisco 857 the other day and found it repeatedly able to sync at a higher rate than my 837. The difference could well have been down to the (newer) ADSL firmware which, in the 837, is not upgradable. Imagine my disappointment when I then discovered the 857 doesn't support IPv6... The phrase 'Giveth with one hand, taketh away with the other' springs to mind... now at least: at the time it was something a bit stronger!  Grin
Mathew
dave
Plusnet Staff
Plusnet Staff
Posts: 12,170
Thanks: 19
Fixes: 1
Registered: ‎04-04-2007

Re: IPv6 routing/connectivity gone awry today?

Moving you over to Max Premium for the month which should give you 832kbps up. Should take effect sometime tomorrow morning. You may need to reboot the router for the change to take effect.
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

That's great, thanks Dave. It'll certainly give some much needed headroom!
Mathew
MJN
Pro
Posts: 1,314
Thanks: 161
Fixes: 5
Registered: ‎26-08-2010

Re: IPv6 routing/connectivity gone awry today?

Dave,
I can confirm there was a forced resync at ~0330hrs and I now have an upload sync of 704kbps and throughput of around 650bkps so that extra bit of headroom will be a real help - thanks!
Mathew