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Level 2: Rookie

DHCPv6 prefix delegation not working on LH1000

I can't find anyone at Telstra that can comment on this. I just keep getting bounced from department to department with no end in sight (4 hour queue so far...). And Platinum support just redirects to normal support. Happy to pay for a solution to this.

 

In short, it seems LH1000 does not pass on the assigned prefix and will respond with "no prefix" or "no address" available when prefix delegation is requested. Which means IPv6 only works with devices directly connected to the modem/switch. Any routers will not be able to use IPv6 networking when connected to this modem.

 

My understanding, from various forums, is that the DJA0231 version does support this. If so, how do swap my modem for the proper model?

 

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9 REPLIES 9
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Level 24: Supreme Being
Level 24: Supreme Being

Re: DHCPv6 prefix delegation not working on LH1000

I have been unable to get IPv6 working on  a router connected to either the LAN of the the LH1000 or the DJA0231 of the modems operating in normal mode. Both provide an IPv6 and prefix length to the WAN of the router and from this the router should be able to work out the prefix.

 

Are you using the LH1000 in normal or Bridge mode? 

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Level 2: Rookie

Re: DHCPv6 prefix delegation not working on LH1000

In normal mode.  Bridge mode would break 4g backup and possibly my landline.

 

I've got the tcp dumps and it shows the modem responding with no address available.  I also took a dump from Win10 to see how it's working.  And it's *also* is getting no address available.  However, Win10 then uses Multicast DNS to figure out it's IP address is.  It seems DHCPv6 is completely broken on this modem?

 

 

 

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Level 2: Rookie

Re: DHCPv6 prefix delegation not working on LH1000

@cf4 have you managed to talk to Telstra about this? I called Platinum support, they didn't answer, got transfered to BigPond Support which said it was fault which then transferred me to ADSL faults, which was wrong, so i get transferred to NBN faults which transfer me to Business Support, who refuse to look at this even though I'm a business customer and finally I end up at a different NBN fault team that literally didn't not speak English.   This is just crazy. 5 hours!

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Level 24: Supreme Being
Level 24: Supreme Being

Re: DHCPv6 prefix delegation not working on LH1000

I haven't tried to talk to Telstra about this as it is not causing any problems in my network. I was only experimenting with connecting the router to the Telstra modem. 

 

If you don't have a DSL connection you could use your router as the main router and connect the Telstra modem to your router's LAN port. The 4G backup want work but the phone should still work.

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Level 2: Rookie

Re: DHCPv6 prefix delegation not working on LH1000

That is an interesting idea - if i get another modem as primary WAN.  Then setup the LH1000 as failover WAN on the USG.  Would voice work that way?

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Level 2: Rookie

Re: DHCPv6 prefix delegation not working on LH1000

I found an old DJA0230 lying around so I got all excited.  I've put it into bridge mode and worked immediately except still no IPv6.  /sigh   I suspect mac id filtering or something on their end which is weird since they are running it over IPoE.  I tried disabling rapid commit but that didn't do anything.

 

It seems Telstra is just going through the motions of saying "look we have IPv6" but not really providing a proper IPv6 layer.  Only Telstra modems are "allowed" get IPv6 prefixes.  What's the point of handing out a /56 prefix to a single modem that you can't configure?

 

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Level 24: Supreme Being
Level 24: Supreme Being

Re: DHCPv6 prefix delegation not working on LH1000

Voice would still work with the Smart modem connected to LAN port of the main modem providing main modem does not have SIP ALG enabled.

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Level 2: Rookie

Re: DHCPv6 prefix delegation not working on LH1000

This works in bridge mode?

 

I've managed to get IPv6 working on the USG with DJA0231 in bridge mode.  The trick:
* need to *disable* rapid-commit on the USG

* need to *disable* IPv6 before switching to bridge mode!!  This is key.

 

I suspect there are a bunch of bugs at play.

1) if you don't disable IPv6 on the modem before switching to bridge mode - it still acts as a router and wont pass on the /56.

2) the USG gets confused which DHCPv6 message to listen to.  One is from Telstra server (correct one) and one is from the router (with nothing to assign).  It then ignores then Telstra one for some reason.  (Ubiquiti support is looking into this).

 

Next step is going get 4G and VOIP working.

 

I've tried hooking up a LH1000 in router mode to the USG-WAN2.  But I couldn't get it to talk to anything.  4G is connected and IP assigned to the modem - but no traffic flows.

 

VOIP is also not connecting this way Smiley Sad  It seems this is IPv6 only?   

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Level 24: Supreme Being
Level 24: Supreme Being

Re: DHCPv6 prefix delegation not working on LH1000

You could try changing the PDP type to IPv4v6. In this mode the the modem gets both an IPv4 and IPv6 address on the WAN.

 

I have mentioned in other posts that IPv6 has to be turned off as well as set to  bridged for modem to function correctly in bridge mode. Leaving IPv6 on when modem is used as an access point also causes problems.

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