Building a Linux IPv6 DNS Server
In our IPv6 network, we presented two application servers: Apache as a Web server and VideoLan for video streaming. To test IPv6 name resolution when streaming a video, a user on client node pc5 accesses the video-streaming server on pc3. The video server is on pc3 (fec0::1:250:b7ff:fe14:5768), and the video client is on pc5 (fec0::1:250:b7ff:fe50:7c). Sniffing the network communications on pc5 with tcpdump, we captured packets from the video stream. Here is a portion of the trace:
% tcpdump ip6 # only trace IPv6 traffic, must be run as root or setuid root [snip...] 02:09:26.716040 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.735805 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.735971 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.736082 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.755810 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.755935 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316 02:09:26.775787 fec0::1:250:b7ff:fe14:5768.32769 > fec0::1:250:b7ff:fe50:7c.1234: udp 1316
The video is displayed properly using X11 output on a Linux X server; Figure 2 shows a capture from the stream.
IPv6 is becoming a reality. For the next few years, we will need to be able to support both IPv4 and IPv6 on our servers before the complete transition to IPv6 occurs. We need different pieces of the puzzle to achieve a full migration to IPv6, and one essential piece is an IPv6-compliant BIND implementation.
Ericsson Research Corporate Unit for approving the publication of this article. Open Systems Lab for supporting our work with Linux and IPv6. Simon Jubinville, Open Systems Lab, for his reviews.
BIND Manual: www.crt.se/dnssec/bind9/Bv9ARM.html
Comparison of AAAA and A6: www.ietf.org/proceedings/02mar/I-D/draft-ietf-dnsext-aaaa-a6-01.txt
DNSSEC and IPv6 A6: ftp.rfc-editor.org/in-notes/rfc3226.txt
DNSSEC Signing Authority: ftp.rfc-editor.org/in-notes/rfc3008.txt
IPv6 Linux Implementations: /article/5468
IPv6 Support for DNS: www.ietf.org/rfc/rfc2874.txt
IP Version 6 Addressing Architecture: www.rfc-editor.org/rfc/rfc2373.txt
Linux Kernel: www.kernel.org
“Supporting IPv6 on a Linux Server Node” by Hbrahim Haddad and Marc Blanchet, LJ, August 2002: /article/4763
David Gordon (David.Gordon@Ericsson.ca) is a computer science intern at Ericsson Research—Open Systems Lab. He is completing his undergraduate studies in Computer Science at Sherbrooke University. His research interests include security, next-generation IP networks and wireless technologies.
Ibrahim Haddad (Ibrahim.Haddad@Ericsson.com) is a researcher at the Ericsson Corporate Unit of Research in Montréal, Canada, involved with the system architecture of third-generation wireless IP networks.
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One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
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With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
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