IPV6 drops, ping failing, tracert working: ?Routing table problem?

[PabloAbonia]

I've recently installed the latest Merlin version for the rt-AC56U, and for the most part it works well (after clearing the nvram that is).

The one odd problem I am running into is with native IPV6. After a day, my Windows 7 devices and IOS devices lose IPV6 connectivity. nslookup queries demonstrate appropriate IPV6 addresses (save for one occasion when .local was being appended).

Here is where it gets odd. All devices demonstrate IPV6 addresses, which can be found be the logs in the router, ipconfig on Windows7, and an IPV6 app on ios.
If I ping an address it fails and the Windows7 devices indicate no IPV6 connectivity (they have addresses and they point to the correct lan-local ipv6 gateway address). No DNS is listed for IPV6, while one is listed for IPV4. However if I tracert to the same address, suddenly IPV6 heals itself, and I can use it again. Given that tracert uses TTL while ping does not, I wonder if the routing table is getting altered in such a way that I can no longer see it.

I would note that I have DISABLED the wireless bands, and I am using it solely as the router connecting directly to the cable modem SB6141. Even without the wifi running, its seems somewhat hot 70C. I've already had to replace cables to 5e versions to prevent some odd problems with nearby sites have poor bandwidth and sites further away tolerating it without difficulty.

Thank you for you thoughts,

Pablo

 

[PabloAbonia]

I've figured out one of my issues (incorrect MTU), but still have a ways to go to get IPV6 working properly.

1. I have ios devices that use mdnsresponder, and by default "use-ipv6" in avahi-daemon.conf is set to no. I've resorted to a timed kill after the system starts followed by restarting it with my modified config file. As a suggestion here, could we default the config file to yes if ipv6 is being used.

2. Also, can the DNS be set to include the routers IPV6 address as well as the IPV4 address. As it doesn't right now, tests via test-ipv6.com fail and complain about my DNS server (9/10 OK)

Pablo

P.S. is ipsec really going away for the RT-AC56U? I'm not quite skilled enough to recompile it as noted at Merlin GITHUB site, and would mean that I would be stuck
at the current version for a while.

 

[stevocz]

for me works firmware 40.

 

[RMerlin]

P.S. is ipsec really going away for the RT-AC56U? I'm not quite skilled enough to recompile it as noted at Merlin GITHUB site, and would mean that I would be stuck
at the current version for a while.

Yes. The new Parental Control / QoS engine is far more valuable than IPSec for the intended target audience - home users. The two are not compatible.

 

[scotte]

2. Also, can the DNS be set to include the routers IPV6 address as well as the IPV4 address. As it doesn't right now, tests via test-ipv6.com fail and complain about my DNS server (9/10 OK)

It should work out of the box as long as your provider is advertising them and your client O/S is working right and supports recursive DNS server discovery. For Linux, you can use the 'rdnssd' package. For any other O/S other than Linux, you are on your own (I don't use them so know nothing about them).

You can also just manually modify your /etc/resolv.conf or create a script to do so, prepending upstream DNS servers. I ran this way for quite a while. Again, assumes Linux - no clue for anything else.

'rdisc6' is a great tool for debugging this stuff, it's part of the 'ndisc6' package on Debian distributions.

 

[PabloAbonia]

Yes. The new Parental Control / QoS engine is far more valuable than IPSec for the intended target audience - home users. The two are not compatible.

OK, that's unfortunate as I use VPN services to connect to work often and I'm pretty sure they use ipsec (Cisco Anyconnect & Juniper Network). Regardless, I think I've compiled it correctly, but I don't know how to disable disable the BWDPI option properly. A pointer in the correct direction would be appreciated.

Thanks,

Pablo

 

[RMerlin]

OK, that's unfortunate as I use VPN services to connect to work often and I'm pretty sure they use ipsec (Cisco Anyconnect & Juniper Network). Regardless, I think I've compiled it correctly, but I don't know how to disable disable the BWDPI option properly. A pointer in the correct direction would be appreciated.

Thanks,

Pablo

It depends on whether your compile requires additional kernel options. This is what is causing compatibility issues, therefore if you compile your own kernel, make sure BWDPI is disabled in target.mak for the target router.