• A rack switch removal ordeal

    I recently needed to remove a couple of decommissioned switches from one of our data centres. This turned out to be quite an ordeal. The reason? The ill-conceived way the rack mount brackets used by most data centre switches are designed. In this post, I will use plenty of pictures to explain why that is, and propose a simple solution on how the switch manufacturers can improve this in future.

  • Validating SSH host keys with DNSSEC

    We have all done it. When SSH asks us this familiar question:

  • Enabling IPv6 on the Huawei ME906s-158 / HP lt4132

    Last year I wrote a post about my difficulties getting IPv6 to work with the Huawei ME906s-158 WWAN module. I eventually gave up and had it replaced with a module from another manufacturer.

  • IPv6 roaming in the United States

    I spent some time in the United States last month. Equipped with SIM cards from both Tele2 Sweden (MCCMNC 24007) and Telenor Norway (MCCMNC 24201), I set out to test IPv6 while roaming, as I usually do while abroad.

  • IPv6 roaming in Sweden

    I attended the Netnod Tech Meeting 2017 in Stockholm earlier this week. As I usually do when when going abroad, I spent some time testing to what extent IPv6 works while roaming in the various PLMNs I have access to.

  • IPv6 roaming in Czechia

    I spent this weekend in Czechia. As I usually do when when going abroad, I spent some time testing to what extent IPv6 works while roaming in the various PLMNs I have access to.

  • Huawei ME906s-158 (a.k.a. HP lt4132): Linux and IPv6 support (or lack thereof)

    UPDATE 2018-12-01: The parts about missing IPv6 support in this post is outdated, see this post for updated information.

  • Update: GitHub Pages, Fastly, and IPv6

    When I created this blog a couple of years ago, I was disappointed to find out that the GitHub Pages service (GHP) did not support IPv6. This was due to the fact that GHP’s CDN provider Fastly didn’t support IPv6.

  • IPv6 roaming in the United Kingdom

    Earlier this week I visited the United Kingdom to attend the excellent UKNOF36 meeting.

  • IPv6 roaming in Belgium and Romania

    I briefly visited Belgium and Romania last month. Using SIM cards from Tele 2 Sweden and Telenor Norway, both of which support the dual-stack IPV4V6 and IPv6-only IPV6 PDP context types, I spent some time testing whether or not I was able to get working IPv6 Internet connectivity while roaming in the various available PLMNs.

  • IPv6 roaming in Sweden

    UPDATE 2017-10-15: The information in this post is outdated, see this post for an updated version.

  • IPv6 support in the PlayStation 4

    The other day, I noticed with great interest that my PlayStation 4 was using IPv6 to communicate with the Internet. I’m fairly certain that this behaviour is new, so I decided to investigate.

  • IPv6-only data centre RFCs published

    I’m very pleased to report that my SIIT-DC RFCs were published by the IETF last week. If you’re interested in learning how to operate an IPv6-only data centre while ensuring that IPv4-only Internet users will remain able to access the services hosted in it, you should really check them out.

  • Norwegian IPv6 year in review

    2016 is soon approaching. In this post I’ll take a look in the rear-view mirror to see how well we did in Norway with regards to IPv6 deployment in 2015. I focus on the status on the end-user side of things, that is, the extent of IPv6 deployment amongst Norwegian ISPs. This is due to the fact that my employer Redpill Linpro mainly provide managed services to content providers, so the traffic entering our dual-stacked data centres can only tell a story about how the ISPs are doing.

  • IPv6 network boot with UEFI and iPXE

    Here at Redpill Linpro we make extensive use of network booting to provision software onto our servers. Many of our servers don’t even have local storage - they boot from the network every time they start up. Others use network boot in order to install an operating system to local storage. The days when we were running around in our data centres with USB or optical install media are long gone, and we’re definitively not looking back.

  • Evaluating DHCPv6 relays

    One of the few remaining IPv4-only services here at Redpill Linpro is our provisioning infrastructure, which is based on PXE network booting. I’ve long wanted to do something about that. Now that more and more servers are shipping with UEFI support, I am finally in a position to start looking at it.

  • SIIT-DC support in Varnish Cache through libvmod-rfc6052

    Here at Redpill Linpro we’re big fans of the Varnish Cache. We tend to put Varnish in front of almost every web site that we operate for our customers, which goes a long way toward ensuring that they respond blazingly fast - even though the applications themselves might not always be designed with speed or scalability in mind.

  • Making a Homenet router out of OpenWrt

    This post provides a step-by-step guide on how to take a residential gateway running OpenWrt, installing the software from the Hnet project on it, and finally converting it to be a full-fledged Homenet router. The post is quite long, but don’t let that put you off - it’s only because I go through the process in minute detail. The entire conversion process shouldn’t take you more than 10-15 minutes.

  • Cisco UCS, multi-queue NICs, and RSS

    The other day one of my colleagues at Redpill Linpro asked me to help him figure out why a web cache server started responding slowly during a traffic peak. My colleague was scratching his head over the problem, because although the traffic level was unusually high for the server in question, it was nowhere close to saturating the server’s 10 Gb/s of available network bandwidth:

  • Homenet - the future of home networking

    Today’s residential home networks are quite simple. They usually have a single Internet connection, which is plugged in to the WAN port of a residential gateway. The gateway will typically feature a few wired Ethernet ports and a wireless access point, which are in most cases bridged together to form a single layer-2 LAN segment. The LAN segment is configured with private IPv4 addresses; in order to let the hosts and devices on the LAN segment to communicate with the IPv4 Internet, the gateway will perform IPv4 NAT.

  • IPv6 mobile roaming: possible or not?

    Since 2012 I have been voting with my wallet, opting to only use mobile providers that give me IPv6 connectivity. To begin with, I was a customer of Network Norway. They were kind enough to include me in their IPv6-only pilot with DNS64 and NAT64. Unfortunately, Network Norway’s fate was to be acquired multiple times, causing their IPv6 pilot to lose momentum due to the loss of key technical personnel. The IPv6 pilot has not yet transitioned to a production service.

  • Working around GitHub Pages and Fastly's missing IPv6 support using Apache mod_proxy

    UPDATE 2017-07-31: The information in this post is no longer accurate; GitHub Pages and Fastly now do support IPv6.

  • First post

    So I’ve finally created my own blog, and you’ve found it, somehow. Congratulations! Expect only posts about technology - networking, data centres, open source software, reports from conferences I attend, et cetera. Essentially, various stuff I play around with both at home and at my workplace Redpill Linpro.

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