IPv6, issues and nginx
This would be a bit long in the tooth post about #IPv6, it’s uptake in India, potential solutions for the interim solution and little bit of Debian news as well.
First, get the good news out-of-the-way, Debian Jessie is slated to be released around April (at least the hope is). This was mentioned by Niels Thykier on the debian-devel-announce mailing few days back. One can find the work-in-progress release notes here. What I am excited about is that finally we should be able to install Debian in UEFI machines with some caveats, see the Notes, specifically this part :-
It is now possible to install PCs in UEFI mode instead of using the legacy BIOS emulation.Note that this does not include support for UEFI Secure Boot.
I would still need to search around a bit because would be looking for a DOS based machine which has good graphics, memory and hardware and has a good build. Only time will tell when that happens.
Also getting BTRFS as a technology preview would also be good although as it has been shared as a Technology preview dunno what to make of it. Having automatic checksumming for each file and other benefits which BTRFS is supposed to bring, it would be cool if it lives upto it. I did check about it a few months back to still find some issues there, it does have some interesting possibilities going ahead.
On the week-end I had some time and hence tried to explore nginx to discover that for some reason it didn’t install on my system. I immediately filed the bug which was promptly taken to task as had raised the severity only to later realize from people that it was due to my not taking/using IPv6. This prompted me to see if I shared about IPv6 before only to see that had made a very short note about 3 years back.
While that was the theoretical part, let me share a bit of the practical experience that time as well. I had a D-Link 502T which was an IPv4 device. Both during Debian Squeeze installation as well as subsequent wheezy installation, I had very flaky net connectivity when trying to use and browse Internet. The reason was pretty simple, the virtual network interface became IPv6 but neither my network-card/lan card or my modem or my ISP were IPv6, so probably lot of dropped packets and lot of latency. I should have run wireshark to see what was happening but at that point getting a stable connection was the priority, I checked Debian’s IPv6 wiki page and turned off IPv6.
I also had to remove entries from /etc/dhcp/dhclient.conf as well to have a smooth working network connection as well :-
request subnet-mask, broadcast-address, time-offset, routers,
domain-name, domain-name-servers, domain-search, host-name,
netbios-name-servers, netbios-scope, interface-mtu,
What is missing therein are
dhcp6.name-servers, dhcp6.domain-search, having them again gives a flaky connection.
Also did similar changes in ufw as well :-
$cat /etc/default/ufw [2:16:57]
# Set to yes to apply rules to support IPv6 (no means only IPv6 on loopback
# accepted). You will need to 'disable' and then 'enable' the firewall for
# the changes to take effect.
Just commenting on IPv6 in ufw was good enough.
Three years have gone by, let me see what changes have been made in the interim :-
a. About 8 months back I got a newish retail modem+router – a DSL-2750u, while this is supposed to be an IPv6 modem+router and there is even an IPV6 check box page at Setup > LAN IPv6 > Enable DHCPv6 Server which I had to un-check. – So as far as the modem is concerned, it is IPv6 ready.
b. Network Card – The in-built ethernet card is still IPv4. That would take another couple of years as and when this workstation dies out. Gigabit IPv6 ports are becoming common now and in 2-3 years, I suppose you will even find them in low-end motherboards as well.
c. My ISP – Saw this http://www.ipv6-test.com/stats/country/IN . As can be seen by the graph IPv6 is going to take quite a long time to take off in the country.
Then I’m sure you scrolled down and saw ‘Top 25 internet service providers for IPv6 in India (Feb 2015)’
The interesting part of the list shared is that at the top is Hurricane Electric. AFAIK they aren’t a regular ISP like others on the list. They are one of the biggest free Tunnel brokers. The sort of job they do is akin to a translator, what they do is make a tunnel to transmit IPv6 packets in an IPv4 environment. Many SOHO as well as business users use them. You will need such services as you want to migrate your services to IPv6 while ISP’s still struggle to replace their old equipment. What seemed interesting is that my ISP, the once public behemoth ‘BSNL’ is not too far down in the dumps and this has good omens. I do hope that at sometime they make a switch to pure IPv6 at least to the local data centre/exchange so any tunneling need (if at all needed) would become the ISP’s headache.
If ISP’s have to pay for tunneling (which they should be doing) they will also be motivated to get their infrastructure IPv6 ready. There would be a bit of overhead as the address space is being quadrupled (from 32 bits to 128 bits) as well as a bit of latency (which better smarter networking products with better processors, cache and algorithms could minimize), how and when the migration will become seamless is really upto the ISP.