I was looking thru some posts and found this information to speed up browsing in firefox. I am running Suse 9.0 with Firefox. I have made the adjustments to the about:config in firefox. However I am curious about this IPv6 value. From the posts I have seen, am I correct in assuming that if you disable this IPv6 setting that the browser will be faster? Apparently, it is supposed to be in the /etc/modules.config. I went into terminal as root to that directory. I opened the /etc/modules.config with pico. There was no information in that file. Is there supposed to be information in that file? One of the posts I read said that you had to enter the following information into that file: alias net-pf-10 off? I understand that is supposed to turn off that IPv6 value. Does this sound right to anyone. I was going to try and see what happened but stopped when I saw that there was no information in the /etc/modules.config. Am I on the right track or not?

Thanks
Frank

the problem with slow internet browsing is caused by DNS servers that return answers for A (ipv4) record queries, but ignore queries for AAAA (ipv6) records.


disable ipv6 in the kernel:
open terminal window then as a root enter the following commands:
echo "alias net-pf-10 off" >> /etc/modprobe.conf
echo "alias ipv6 off" >> /etc/modprobe.conf

reboot

Next enter in your browser address bar:
about:config
set the filter for ipv6
next doubleclick on
network.dns.disableIPv6 so the value will change from false to true.

The above will work and internet browsing will be faster under one condition: that you have optimized other values of the network protocol:
If you will not observe any improvement then reason can lay in other not resolved issues.

In general, disabling ipv6 may help but it will never deteriorate your network. That is why people often kill ipv6.

Of course I would suggest other tweaks too: MTU discovery, window scaling, timestamp, sack and so on.

Hope that will help.

Thanks for the detailed directions. I will give it a try.

Thanks
Frank

I had the same problem but after adding those entries in /etc/modprobe.conf,
the browsers refresh the pages very fast. The DNS queries are with type =1
(A, IPV4 address) and the response from nameserver is seen immediately.

However, there are some applications that still use IPV6 address in their
queries. I have configured evolution (as a POP3 mail client) to get emails
from gmail and here is the capture (from ethereal!)

15 31.33984 192.168.1.102 -> 192.168.1.1 DNS C pop.gmail.com. Internet AAAA ?
16 0.07952 192.168.1.1 -> 192.168.1.102 DNS R pop.gmail.com. Internet Addr 64.233.171.111
17 4.92045 192.168.1.102 -> 192.168.1.1 DNS C pop.gmail.com. Internet AAAA ?
18 0.09158 192.168.1.1 -> 192.168.1.102 DNS R pop.gmail.com. Internet Addr 64.233.171.111
19 4.90785 192.168.1.102 -> 192.168.1.1 DNS C pop.gmail.com.hsd1.ca.comcast.net. Internet AAAA ?
20 5.05421 192.168.1.102 -> 192.168.1.1 DNS C pop.gmail.com.hsd1.ca.comcast.net. Internet AAAA ?
21 5.01862 192.168.1.102 -> 192.168.1.1 DNS C pop.gmail.com. Internet Addr ?
22 0.09515 192.168.1.1 -> 192.168.1.102 DNS R pop.gmail.com. Internet Addr 64.233.171.111

If we look at the details of one packet (15 from above), we can see the query type is 28 (for
IPV6 address)

DNS: ----- DNS Header -----
DNS:
DNS: Query ID = 31116
DNS: Opcode: Query
DNS: RD (Recursion Desired)
DNS: 1 question(s)
DNS: Domain Name: pop.gmail.com.
DNS: Class: 1 (Internet)
DNS: Type: 28 (IPv6 Address) <------------ IPV6
DNS:

Mozilla for example sends the request correctly, as seen from this

DNS: ----- DNS Header -----
DNS:
DNS: Query ID = 38534
DNS: Opcode: Query
DNS: RD (Recursion Desired)
DNS: 1 question(s)
DNS: Domain Name: ads.rediff.com.
DNS: Class: 1 (Internet)
DNS: Type: 1 (Address)
DNS:

In spite of disabling IPV6 through modprobe.conf, why are some applications
still sending DNS queries with IPV6 address ? Even if it were to send those,
my name server seems to be responding right away and still the client
sends the query after another 5 seconds?

How do we circumvent this problem?

you would have to configure application so it will not try to use IPv6.
For example:
in mozilla it will be
network.dns.disableIPv6

However your kernel now does not know what IPv6 is so it can't proccess these requests and IPv6 should be ignored

hi
are these set of instructions for a IPV6 network or IPv4 network .. i use dial up with IPV4 address ...i dont have a IPv6 for ppp0 .. if i disable IPV6 .. will it anyway matter ..
and also i wish to ask abt MTU .. my current MTU is 264 .. mine is a wireless interface .. tht is .. i connect through mobile ..
wot MTU can give me better performance .. dast n relaible .. what are other tweaks i can attempt to improve my browsing speed ?
thnks n regards