IPv6 connecting issues Can't browse certain website

[James Yang]

Hello guys!

I recently started trying out IPv6,and my ISP just updated its VDSL router as well,I hook it up to my new Synology RT1900ac router(connecting WAN through PPPoE),but here comes problem.

The biggest is that I can't connect to certain website,like YAHOO!,sometimes even Google,this happens after I hooked it up with the RT1900ac router,I don't know what I've done wrong...(I can ping it,but just can't browse the website through the browsers)

I have tried just hooked my VDSL modem(have IPv6 enable as well)and boom!YAHOO,GOOGLE,everything is fine!But when I connect it back through RT1900ac,suddenly it just won't work anymore.

 

If anyone's familiar with RT1900ac,please you must tell me how can I get it work.

I have googled and changed my PC's MTU to 1492 and after changing,there's a short period that I can connect to YAHOO,GOOGLE,but then PC changed back to 1500 even though I type the cmd command added store=persistant.

Anyone know how to change or set the RT1900ac's LAN DHCP MTU?'cause I didn't find the option anywhere within settings.

 

Much appreciated for any possible solution.

[Lurick]

You don't need to adjust the MTU size, IPv6 will determine the smallest MTU on the path and adjust accordingly. As for not being able to access the websites it's probably due to the fact that the router doesn't have any IPv6 DNS servers being given to it. So you'll either have to find where to set those in the router for handing out to clients when it passes out addresses or manually set it on the computer itself.

[jeffmeyer5295]

I agree with @Lurick that it is a DNS issue, if you can ping the website but your browser is not giving you the website, it is just not being directed correctly. 

[James Yang]

1 minute ago, Lurick said:

You don't need to adjust the MTU size, IPv6 will determine the smallest MTU on the path and adjust accordingly. As for not being able to access the websites it's probably due to the fact that the router doesn't have any IPv6 DNS servers being given to it. So you'll either have to find where to set those in the router for handing out to clients when it passes out addresses or manually set it on the computer itself.

First part,got it.But second part,Currently my IPv6 DNS setting is DHCPv6 as well,and I have set my ISP's DNS server as main one and Google's IPv6 DNS as second,though my VDSL modem's IPv6 is stateless...

[Lurick]

3 minutes ago, James Yang said:

First part,got it.But second part,Currently my IPv6 DNS setting is DHCPv6 as well,and I have set my ISP's DNS server as main one and Google's IPv6 DNS as second,though my VDSL modem's IPv6 is stateless...

Hmmm, what is the ouput of 'ipconfig /all' when you can't access the sites.

 

I was looking at your post and realized you can resolve for a period of time but then it stops so now I'm wondering if something else is to blame. I assume if you disable IPv6 in Windows then everything works correctly since it's going over just IPv4 but windows should be falling back to that if IPv6 fails.

[James Yang]

9 minutes ago, Lurick said:

Hmmm, what is the ouput of 'ipconfig /all' when you can't access the sites.

 

I was looking at your post and realized you can resolve for a period of time but then it stops so now I'm wondering if something else is to blame. I assume if you disable IPv6 in Windows then everything works correctly since it's going over just IPv4 but windows should be falling back to that if IPv6 fails.

So,I've set both my router's and PC's IPv6 DNS to OpenDNS's and Google's,Google website now is able to connect,but still no sign of Yahoo...I was originally leaving IPv6's DNS empty,using stateless mode,'cause my ISP service told me that I don't need to do anything about IPv6's DNS...but now here we are...

[Lurick]

7 minutes ago, James Yang said:

So,I've set both my router's and PC's IPv6 DNS to OpenDNS's and Google's,Google website now is able to connect,but still no sign of Yahoo...I was originally leaving IPv6's DNS empty,using stateless mode,'cause my ISP service told me that I don't need to do anything about IPv6's DNS...but now here we are...

Yah, stateless doesn't hand out DNS information iirc, stateful/DHCPv6 does.

 

I assume if you do a ping to yahoo.com it resolves it as 2001:4998:44:204::a7 yes?

[James Yang]

1 minute ago, Lurick said:

Yah, stateless doesn't hand out DNS information iirc, stateful/DHCPv6 does.

 

I assume if you do a ping to yahoo.com it resolves it as 2001:4998:44:204::a7 yes?

Yeah.

[James Yang]

Though,It seemed problem solved,but in my further discoveries,that it mightn't be my problem,'cause I connect to my ISP's VDSL router and uses IPv6 connection,suddenly a lot of website like PCmeg,Tom's Hardware...etc,cannot ping or access the page,I guess there's problem with my ISP as well...Networking is really hard...

[James Yang]

Ugh,after so much effort for trying to find out what's wrong with IPv6,I've decided to stick with IPv4 for now.The only reason that drove me to trying out IPv6 was that I heard IPv4's address soon to be run out...so...yeah,apparently it's still have plenty to use.

[Lurick]

10 hours ago, James Yang said:

Though,It seemed problem solved,but in my further discoveries,that it mightn't be my problem,'cause I connect to my ISP's VDSL router and uses IPv6 connection,suddenly a lot of website like PCmeg,Tom's Hardware...etc,cannot ping or access the page,I guess there's problem with my ISP as well...Networking is really hard...

Yah, it can be hard to implement a large change and get it right on the first try. Your ISP is probably still rolling things out or just finished rolling it out recently which will take some time to get everything fixed.

 

IPv4 addresses have been rumored to be "running out" for 15+ years now, lol.

[James Yang]

2 minutes ago, Lurick said:

Yah, it can be hard to implement a large change and get it right on the first try. Your ISP is probably still rolling things out or just finished rolling it out recently which will take some time to get everything fixed.

 

IPv4 addresses have been rumored to be "running out" for 15+ years now, lol.

Well,Dang,15+ years and it's still standing,I guess I don't need to bother myself...It's just fun to actually try out something you never used before.I had few e-mails with my ISP,though they didn't directly confirm that something's wrong with them,but they didn't deny it...maybe few months later,it'll be resolved...

[Lurick]

Just now, James Yang said:

Well,Dang,15+ years and it's still standing,I guess I don't need to bother myself...It's just fun to actually try out something you never used before.I had few e-mails with my ISP,though they didn't directly confirm that something's wrong with them,but they didn't deny it...maybe few months later,it'll be resolved...

Yah, we should have switched to IPv6 long ago but keep coming out with new ways to extend the lifespan of IPv4 address spaces such as carrier grade NAT and whatnot. It took my ISP almost a year to resolve an issue with IPv6 firmware on the modem I had.

[James Yang]

1 minute ago, Lurick said:

Yah, we should have switched to IPv6 long ago but keep coming out with new ways to extend the lifespan of IPv4 address spaces such as carrier grade NAT and whatnot. It took my ISP almost a year to resolve an issue with IPv6 firmware on the modem I had.

Ugh...a year...took them long enough...I'll guess that'll be happen to me as well,perhaps it'll take me two years...

[Lurick]

1 minute ago, James Yang said:

Ugh...a year...took them long enough...I'll guess that'll be happen to me as well,perhaps it'll take me two years...

I would say it all depends on your ISP, they could figure out the issue and get it fixed tomorrow, lol. I would just let it be for now and check every couple of months to see if it's gotten any better.