is there anyone to know how can I close fallback at squid ?
http://ipv6-test.com/
when I check from ipv6 test fallback is running.
I m using ipv6 squid proxy and I want to close fallback support. How can I do this *

As you were told in your other post (where you hijacked a thread), you need to read the "Question Guidelines", because unless you provide DETAILS and tell us what you've done/tried so far, we can't help at all. You say nothing about version/distro of Linux, version of Squid, or anything that you've researched on your own.

And not sure what you even mean by "close fallback".

I m using debian 8 and I tried a line dns_v4_fallback off but its working only at 3.1 version. At the moment squid is running 3.5 and 4.5 version. I tried at everything at conf but its ruunning same. When I tried to my ipv6 status from ipv6-test.com fallback is running. But I m checking some other squid proxies they are closing this option.

if you login ipv6-test.com you will see at the right side fallback option. When I will configure my browser with proxy which I setup squid 4.5 at debian 8 fallback option is running on. How can I close it from squid ?

I dont know how can I explain another way

Still no idea what you mean by "close it from squid", but now that you've provided details and explained things a little, I *THINK* this may answer your question:
https://superuser.com/questions/9947...ther-than-ipv6

That link not works for me.

https://i.hizliresim.com/oX6lVX.png
https://i.hizliresim.com/lqbRZQ.png

with squid fallback option is enabled. with another program its disabled. How can I disable with squid ?

Posting links we can't view doesn't tell us anything. Just saying "not works for me" tells us nothing either. Post the messages HERE; not images. That just makes things harder to read, and unsearchable for anyone else.

And *STILL* no idea what you're talking about. Do you want fallback to work or not? What is this 'another program' you're talking about now? And if you don't want fallback enabled in Squid, then DO NOT ENABLE IT. Simple.

when I m installing 3proxy fallback option is not running when I test the proxy. But when I m installing with squid fallback is running. How can I configure squid without fallback support ?