So You Want to Be a Network Administrator
Thick skin required. Any application or service performance problem incurred will inevitably lead a network administrator having to prove that it’s not a network problem.netlab Release 1.4.1: Cisco ASAv
The star of the netlab release 1.4.1 is Cisco ASAv support: IPv4 and IPv6 addressing, IS-IS and BGP, and libvirt box building instructions.
Other new features include:
- VRRP on VyOS
- Anycast gateway and VRRP on Dell OS10 (with a bunch of caveats)
- Unnumbered OSPF interfaces on VyOS
- Support for all EVPN bundle services
- FRR version 8.4.0
Upgrading is as easy as ever: execute pip3 install --upgrade networklab.
New to netlab? Start with the Getting Started document and the installation guide.
netlab Release 1.4.1: Cisco ASAv
The star of the netlab release 1.4.1 is Cisco ASAv support: IPv4 and IPv6 addressing, IS-IS and BGP, and libvirt box building instructions.
Other new features include:
- VRRP on VyOS
- Anycast gateway and VRRP on Dell OS10 (with a bunch of caveats)
- Unnumbered OSPF interfaces on VyOS
- Support for all EVPN bundle services
- FRR version 8.4.0
Upgrading is as easy as ever: execute pip3 install --upgrade networklab.
New to netlab? Start with the Getting Started document and the installation guide.
Coding Packets the Shazam Edition
https://codingpackets.com/blog/coding-packets-the-shazam-edition
Day Two Cloud Invite: Recording At TopGolf Las Vegas Nov. 30, 2022
If you're headed to AWS re:Invent in Las Vegas, you can catch Ned & me recording a show live. On Wednesday, November 30, 2022, we’ll be at TopGolf with sponsor Prosimo from 4 to 7 pm. Join us to have some fun! Links and drinks, meet fellow engineers building clouds for their companies, and then watch us record the show. Space is limited, so register at prosimo.io. We’ll see you at TopGolf Las Vegas on Wednesday the 30th!
The post Day Two Cloud Invite: Recording At TopGolf Las Vegas Nov. 30, 2022 appeared first on Packet Pushers.
Day Two Cloud Invite: Recording At TopGolf Las Vegas Nov. 30, 2022
If you're headed to AWS re:Invent in Las Vegas, you can catch Ned & me recording a show live. On Wednesday, November 30, 2022, we’ll be at TopGolf with sponsor Prosimo from 4 to 7 pm. Join us to have some fun! Links and drinks, meet fellow engineers building clouds for their companies, and then watch us record the show. Space is limited, so register at prosimo.io. We’ll see you at TopGolf Las Vegas on Wednesday the 30th!Congestion Control Algorithms Are Not Fair
Creating a mathematical model of queuing in a distributed system is hard (Queuing Theory was one of the most challenging ipSpace.net webinars so far), and so instead of solutions based on control theory and mathematical models we often get what seems to be promising stuff.
Things that look intuitively promising aren’t always what we expect them to be, at least according to an MIT group that analyzed delay-bounding TCP congestion control algorithms (CCA) and found that most of them result in unfair distribution of bandwidth across parallel flows in scenarios that diverge from spherical cow in vacuum. Even worse, they claim that:
[…] Our paper provides a detailed model and rigorous proof that shows how all delay-bounding, delay-convergent CCAs must suffer from such problems.
It seems QoS will remain spaghetti-throwing black magic for a bit longer…
Congestion Control Algorithms Are Not Fair
Creating a mathematical model of queuing in a distributed system is hard (Queuing Theory was one of the most challenging ipSpace.net webinars so far), and so instead of solutions based on control theory and mathematical models we often get what seems to be promising stuff.
Things that look intuitively promising aren’t always what we expect them to be, at least according to an MIT group that analyzed delay-bounding TCP congestion control algorithms (CCA) and found that most of them result in unfair distribution of bandwidth across parallel flows in scenarios that diverge from spherical cow in vacuum. Even worse, they claim that:
[…] Our paper provides a detailed model and rigorous proof that shows how all delay-bounding, delay-convergent CCAs must suffer from such problems.
It seems QoS will remain spaghetti-throwing black magic for a bit longer…
Mastodon – Part 3 – statsd and Prometheus
About this series
I have seen companies achieve great successes in the space of consumer internet and entertainment industry. I’ve been feeling less enthusiastic about the stronghold that these corporations have over my digital presence. I am the first to admit that using “free” services is convenient, but these companies are sometimes taking away my autonomy and exerting control over society. To each their own of course, but for me it’s time to take back a little bit of responsibility for my online social presence, away from centrally hosted services and to privately operated ones.
In my [first post], I shared some thoughts on how I installed a Mastodon instance for myself. In a [followup post] I talked about its overall architecture and how one might use Prometheus to monitor vital backends like Redis, Postgres and Elastic. But Mastodon itself is also an application which can provide a wealth of telemetry using a protocol called [StatsD].
In this post, I’ll show how I tie these all together in a custom Grafana Mastodon dashboard!
Mastodon Statistics
I noticed in the [Mastodon docs], that there’s a one-liner breadcrumb that might be easy to overlook, Continue reading
Worth Reading: Troubleshooting EVPN Control Plane
When trying to decide whether to use EVPN for your next data center fabric, you might want to consider how easy it is to configure and troubleshoot.
You’ll find a few configuration hints in the Multivendor Data Center EVPN part of the EVPN Technical Deep Dive webinar. For the troubleshooting part, check out the phenomenal Troubleshooting EVPN with Arista EOS article by Tony Bourke.
Worth Reading: Troubleshooting EVPN Control Plane
When trying to decide whether to use EVPN for your next data center fabric, you might want to consider how easy it is to configure and troubleshoot.
You’ll find a few configuration hints in the Multivendor Data Center EVPN part of the EVPN Technical Deep Dive webinar. For the troubleshooting part, check out the phenomenal Troubleshooting EVPN with Arista EOS article by Tony Bourke.
Palo Packet Captures
Information on running packet captures and debugging commands to follow traffic flows.
An early look at Thanksgiving 2022 Internet trends
"The more you practice the art of thankfulness, the more you have to be thankful for."
— Norman Vincent Peale, American author
The turkey. The sweet potatoes. The stuffing. The pumpkin pie. Yesterday, November 24, 2022, was Thanksgiving Day in the US. A time for families and loved ones to be together and thankful, according to the tradition. Last year, we saw how the US paused shopping (and browsing) for Thanksgiving. So, how was it this year? Not only did we see Internet traffic go down (by 13%) during Thanksgiving dinner, but it was much higher than usual the day before and the day after (the Black Friday effect… so far). There was also a clear, but short, Thanksgiving day effect on e-commerce DNS trends.
We'll have to wait to see what Black Friday looks like.
Let’s start with Internet traffic at the time of Thanksgiving dinner. Although every family is different, a 2018 survey of US consumers showed that for 42% early afternoon (between 13:00 and 15:00 is the preferred time to sit at the table and start to dig in). But 16:00 seems to be the “correct time” — The Atlantic explains why.
That said, Cloudflare Continue reading
How Cloud Computing Adoption Has Accelerated in the Remote Work Era
Our personal and professional lives are fundamentally shaped by technology, and there is, to a growing extent, an increased reliance on cloud computing for remote work today.Cloudflare servers don’t own IPs anymore – so how do they connect to the Internet?
A lot of Cloudflare's technology is well documented. For example, how we handle traffic between the eyeballs (clients) and our servers has been discussed many times on this blog: “A brief primer on anycast (2011)”, "Load Balancing without Load Balancers (2013)", "Path MTU discovery in practice (2015)", "Cloudflare's edge load balancer (2020)", "How we fixed the BSD socket API (2022)".
However, we have rarely talked about the second part of our networking setup — how our servers fetch the content from the Internet. In this blog we’re going to cover this gap. We'll discuss how we manage Cloudflare IP addresses used to retrieve the data from the Internet, how our egress network design has evolved and how we optimized it for best use of available IP space.
Brace yourself. We have a lot to cover.
Terminology first!
Each Cloudflare server deals with many kinds of networking traffic, but two rough categories stand out:
- Internet sourced traffic - Inbound connections initiated by eyeball to our servers. In the context of this blog post we'll call these "ingress connections".
- Cloudflare sourced traffic - Outgoing connections initiated by our servers to other Continue reading
Heavy Networking 657: New VMware Client Connects Users To SASE, SD-WAN (Sponsored)
Today on Heavy Networking, a discussion with sponsor VMware about SD-WAN and SASE. We’re diving into announcements from VMware Explore Barcelona 2022 covering a new SD-WAN client and more. With this client, you’ll be able to connect your users to the SASE cloud with software--no hardware edge box required. We dive into how it works, the network architecture, use cases, and more.
The post Heavy Networking 657: New VMware Client Connects Users To SASE, SD-WAN (Sponsored) appeared first on Packet Pushers.