Posts

At the end of Part 3 I had a working fabric, with the v4 prefix in the global table, failover tested, packets arriving over both ISPs. And one lingering design flaw that I knew about and had been ignoring: my house was originating 100% of the announcements. What actually happens when the house goes dark Let’s follow the chain: The ERs originate the /24 into iBGP, the BRs learn it from them and pass it to their upstreams. The announcement exists because home says it exists. ...

Part 2 was all theory and whiteboard. Two border routers in two VPS providers, two edge routers at home, WireGuard between all of them, OSPF for liveness, iBGP to carry the prefix. Nice boxes, nice arrows (but i have a bone to pick with you Mermaid…) Now let’s actually start building the thing! “the diagram makes sense” and “packets are arriving” turned out to be full of small, stupid, extremely time-consuming problems. ...

At the end of Part 1 I had an ASN, a /24, and absolutely no way to use either one, which made me happy and sad at the same time. A prefix is only useful in the global Internet when some other network accepts it from you and passes it on, but until that happens you just own a number. Comcast over cable was never going to be that provider, so I needed to find someone else who would run BGP with a guy whose infra lives next to the laundry sink and sump pump. ...

I’ve wanted my own Internet address space for a long time. Not “my ISP gave me some statics” space which I’ve had for well over a decade now, but a block that belongs to me, announced into the global routing table by equipment I own, and ideally sitting in the rack in my house. Type the prefix into bgp.tools and see my own ASN sitting there as the origin. How cool! (ok, cool for some, but not most) ...

I am fortunate to have the opportunity to continue working from home during the pandemic. As myself and my family adapt to a new normal in a new working space at home, a way of notifying them when I’m on a call would prove useful. So if you own a Plantronics (now Poly) headset, and have a Philips Hue Bridge with a light, I’ll explain how to build a little one-line script and have it light up when on a call. I love Plantronics (umm… Poly) stuff!!! ...

A couple of months ago I took delivery on my Tesla Model 3 “Speedy”. In the time between placing the order and actually getting the car, aside from being beyond excited, I took a bit of time to learn about the car’s always-connected API and how to use it, and also signed up for off-peak billing from my local utility ComEd. Then I decided to take things to a new level by combining two API’s and making some triggers for charging, so this is the whole point of my post. ...

If you’ve never heard of Twilio before, you’d be surprised to learn that they are the largest backend for services around automated calling services, text messaging (and verification), and are pioneering Software Defined Telephony by use of APIs to route and handle texts/calls/faxes. Is your Uber driver calling you now? That’s Twilio… Got a text from Netflix for a password reset? Yup, that’s Twilio… PagerDuty sending you a SMS alert? You guessed it! ...

If running Lync Server 2010, Lync Server 2013 or Skype for Business Server 2015, and started noticing these in your Lync Server event log sometime between May and June of 2017, while at the same time people can’t share PowerPoints or do Whiteboards / Q&A… Then you’ve fallen victim of a known issue with the May 2017 .NET Framework Security and Quality Rollup affecting the Web Conferencing Service. Luckily, Microsoft detailed two workarounds, one involves getting a new Edge Internal cert, and another involved a registry change. Here’s the details: ...

TL;DR: When dual-homing, make sure both your NICs have the same link speed (1Gb, 10Gb). VMware’s E1000E is 1Gb, and VMXNET3 is 10Gb. Automatic metrics will prefer the 10Gb and that may cause the issue below…. After a power loss over the weekend, two Skype for Business Front-Ends were restarted and the RTCSRV service failed to start. A bit about these machines that’s relevant to the issue: Running Widnows Server 2012 R2 as VMware ESXi 5.5 guests. Collocated Mediation service. Dual-homed, with Data network as default gateway, and Voice network to talk to a Sonus SBC, with service usage limited to the specified addresses for Primary and PSTN in the topology. Certificate stores were in good order, so KB2795828 did not apply. ...

Let’s say it was totally underprovisioned at some point. Just bumping up the RAM won’t give you the performance you expect. Here’s why: You deploy a Server 2012 R2 template with 2GB RAM using your favorite hypervisor and just roll with the Skype for Business or Lync deployment without even thinking about it. Or… let’s say you ask for a VM to be provisioned so you can roll out SfB, and it’s underprovisioned from the start, but changing the resources would take too long so you go ahead with the deployment anyway and just wait for resources to be added later on. No time wasted. How many times has that happened? Plenty to me… ...