LSA

A story behind Facebook Command Runner (FCR) for network devices

https://code.facebook.com/posts/117615485632126/fcr-open-source-command-runner-for-network-devices-/

#Facebook #Opensource #Automation

I believe it comes at no surprise that Python is a Network Automation Engineer toolset' first class citizen.
So it would be nice&wise to stay sharp with your Python skills and PyCon'17 sessions will gladly help you!


#Python #PyCon17

https://www.youtube.com/channel/UCrJhliKNQ8g0qoE_zvL8eVg/videos?flow=list&view=0&sort=dd&live_view=500

Are you ready for another portion of Network@Scale? May edition features the following talks:

* Moving Fast with Facebook's New Long-Haul Network (Henry Kwok, Facebook)

* Scaling for Exabytes (Jason Wilson, Dropbox)

* Automating and Scaling the Edge (Xiaozheng Tie, Facebook)

* A Close Look at Alibaba's High Performance Packet Processing Platform (Haiyong Wang, Alibaba)

* Delivering Terabits of Content: External Considerations (Aaron Klink, Netflix)

* Zero Protocol and TLS 1.3: Low Latency Transport Security at Facebook (Subodh Iyengar, Facebook)

* Facebook CDN: Minimizing Latency and Jitter for Content Delivery (Sumanth Sukumar, Facebook)

* The Very Best of Certificate Transparency (2011-Present) (Kat Joyce and Al Cutter, Google)

* Internet-scale Virtual Networking using IPv6 ILA (Petr Lapukhov, Facebook)

* Delivering IPv6 on Amazon Virtual Private Cloud (Alan Halachmi, Amazon)

* Microsoft IT IPv6 Only - The Path Ahead (Todd Thorson, Microsoft)

* High Altitude Platforms for Rural Backhaul (Adit Sahasrabudhe, Facebook)

* Solving Large Scale Data Center and Cloud Interconnection Problems (Ihab Tarazi, Equinix)

* How Facebook Designs its Own Hardware and Network (Hans-Juergen Schmidtke and Jimmy Williams, Facebook)


PS: Do you know where can I borrow a day to watch them all?

#Facebook #NetworkAtScale #Video

https://code.facebook.com/posts/1468803066504563/networking-scale-2017-recap/

ssh-copy-net is a ssh-copy-id made for network devices.

Our friend and a distinguished networking blogger NetworkOp shares a python script which allows you to copy your public key to the following networking devices
* Cisco IOS-XE
* JUNOS (SRX, MX)
* Arista EOS
* Alcatel SROS
* Dell Force10 OS9
* HP Comware 7
* Mellanox MLNX-OS

Example:
[null@null ~]$ ssh-copy-net 10.6.142.1 juniper
Username: admin
Password:
All Done!

#NetworkAutomation #Python #Netmiko #SSH

https://github.com/networkop/ssh-copy-net

A big 'Harlem Shake' in the SD-WAN world — Cisco set in motion Viptela acquisiton. Why is it big? Mainly because its Viptela, which's been a gem in the USA SD-WAN market.

Literally, US market (as seen by social media) has been divided by Viptela and Silverpeak. And now Viptela is gone, swallowed by Cisco who has IWAN and Meraki already in the SD-WAN portfolio.
Does it mean that IWAN and Meraki failed? Lets leave this debate to Network Collective show

#Video #sdwan #cisco #viptela #networkcollective

http://thenetworkcollective.com/2017/05/off-cuff-cisco-acquiring-viptela/

And we have a coming-out: Facebooks described its new and shiny backbone network (from now on EBB == Express Backbone). Its powered by a TE Controller, Segment Routing and Open/R, could it even be more hipster-ish?

We set the following high-level goals for the project:

- Find a design allowing for incremental deployment of new features and code updates, preferably in fractional units of network capacity to allow for fast iterations.

- Avoiding pitfalls with distributed traffic engineering (RSVP-TE based Auto-Bandwidth), such as inefficient use of network resources and complex convergence patterns under network failures.

- Keep network state lean by leveraging MPLS segment routing at the edges of the network domain.

Now the fun part is that there is no IGP in a way we know it. Its been completly replaced by Open/R.

The article keeps a secret how big is this EBB comparing to the classic backbone, yet the shift plan is formed and it is only a matter of time when the whole Facebook' backbone will operate in this way.

#Article #OpenR #SegmentRouting #Facebook

https://code.facebook.com/posts/1782709872057497/building-express-backbone-facebook-s-new-long-haul-network/

Now if you missed this, just yesterday a Juniper engineer (Kireeti Kompella) sat with some SMM guy and talked for 30 minutes about Self Driving Networks. While the acronym is still SDN, it takes one step further in the insanity of the proposition.

Self-Driven Networks are meant to operate in a long run without human intervention. An Mr. Kompella is driving this one with Juniper.

Sadly, there were no details about how/when or what is going to happen, yet it pleases just listen to Kireeti talking about technologies.

A good question came in the live feed, btw.
Abhijeet Kumar Mishra · Automation and self driving certainly benefits customers, however opportunities for JNCIE network engineers are narrowing down. How will these certifications will enhance opportunities for network engineers.
Yeah man, if Kireeti gives you an advice "stop being CLI-jokey" you better listen to it.

https://www.facebook.com/JuniperNetworks/videos/10158740071320294/

Have you heard about FRRouing?
Free Range Routing is "an IP routing protocol suite for Linux and Unix platforms which includes protocol daemons for BGP, IS-IS, LDP, OSPF, PIM, and RIP." as declared on projects official site https://frrouting.org/

Its a Quagga fork which aims an ultimate goal of making a productive, quality, free TCP/IP routing software package. Currently FRRouting supports BGP4, BGP4+, OSPFv2, OSPFv3, RIPv1, RIPv2, RIPng, PIM-SM/MSDP and LDP as well as very early support for IS-IS.

Just this month Linux Foundation welcomed FRR project under its umbrella [1] and having these guys [2] supporting the project it might be a successful one.

Definitely worth exploring if you are looking for an OpenSource TCP/IP routing system for your linux boxes. Boy, they claim it comes with MPLS (and even EVPN) support.

PS: Russ White is one of the project maintainers =) You can check out his talk in PacketPusher PQ show released 2 days ago [3]

#Opensource #FRRouting

[1] https://www.linux.com/news/2017/4/welcoming-frrouting-linux-foundation
[2] 6WIND, Architecture Technology Corporation, Big Switch Networks, Cumulus Networks, LabN Consulting, NetDEF (OpenSourceRouting), Orange, Volta Networks
[3] http://packetpushers.net/podcast/podcasts/pq-show-112-free-range-routing-ietf-98/

One of the strongest xNOG communities — Irish iNOG — delivered another session INOG::B.

And the topics are hot:
00:00:00 Barry O'Donovan (INEX) BGP Large Communities, RFC 8092
00:14:09 Costi Serban (Independent) Googler, Openflow is not Dead
00:31:07 Laura Nolan (Google) IPv6 Operating Challenges
01:14:40 Cristian Sirbu (iNOG) Close out, thanks, and Logo intro!

#iNOG #Video #IPv6 #Openflow

https://www.youtube.com/watch?v=38vsEtYNVTk&feature=youtu.be

Long time no see, fellows!

Now imagine you need to recap MPLS as a technology with it's various aspects and you only have a weekend to do so.

I would suggest you to start with this talk given on a recent NANOG conference where a speaker outlines most notable MPLS characteristics and applications.
Starting from reasoning behind MPLS technology and up to L3VPNs and resilience techniques, this talk does not cover all of these extensively, but can point you to the areas where you feel like lack of advanced knowledge.

#Video #MPLS #NANOG

https://youtu.be/ktJxcxntjbs

It is remarkable how quickly technology giants like Facebook, Google, Amazon and others became newsmakers No1 in the networking area. Seriously, for 5 breaking news from these guys its only 1 serious announcement from vendor-camp. Keeping the ratio in favor of tech giants meet the roundup of the recent Facebook' even called Disaggregate: Networking. [1]

Last week Facebook held an invitation-only party with very few companies onboarded, among which were Barefoot, Apstra, Canonical and Cumulus. At Facebook, we build our data centers with fully open and disaggregated hardware. This allows us to replace the hardware or the software as soon as better technology becomes available. Because of this, we see compute, storage, and networking gains that scale with our business. We spoke about our latest networking hardware and software — including Wedge 100, Backpack, Voyager, FBOSS and OpenBMC.

As you see, the key topic of this event was disaggregation between software and hardware components. I urge you to watch the keynote video as it lays out the vector of the whole event and helps one to understand why disaggregation was mandatory to large-scale companies like FB.

Here is the list of the talks happened there:
- Managing a Hybrid Network [by FB] (Don't spend too much time on this talk, it is about Robotron tool, which is much better explained in this deicated article [2])
- Wedge100 and Backpack: From the Leaf to the Spine [by FB]
- Why Forwarding Planes will be Programmable: New Paradigms and Use Cases in Networking [by BAREFOOT] (exceptional talk by Barefoot on what is P4 programmable chip and its benefits)
- Open Networking Landscape Overview [by BigSwitch]
- Disaggregating The Network OS With Ubuntu [by Canonical]
- OpenBMC: An Open Software Framework for BMC [by FB]
- Experiences Deploying Disaggregated Solutions [by Cumulus]
- The Disaggregated Network Stack [by Snaproute]
- Making Open Networking Easy to Build, Deploy and Operate [by Apstra]
- Voyager: Opening Layer-1 [by FB]
- Network Emulation: Testing Switch Software at Scale [by FB]

#Video #Facebook #Automation

[1] https://code.facebook.com/posts/1887543398133443/disaggregate-networking-recap/
[2] https://research.fb.com/robotron-top-down-network-management-at-facebook-scale/

A burden of many #NETCONF articles and tutorials is that they are often silent about the #YANG part. This is why we would like to highlight this post by Michael Kashin called ""Getting Started With NETCONF and YANG"" [1]. Not only this article covers the basics of network elements configuration via NETCONF (particularly via python ncclient module [2]) but also extends to the YANG models definition with practical examples.

Michael uncovers how heavily NETCONF relies on YANG models, how one can download models straight from a network element itself and how to repsent YANG models in a human-readable tree-view with pyang [3] support.

In its closing you'll see a little bit more advanced technique of building a python module based on the downloaded YANG models. Later this python module is used to create a configuration XML delivered via NETCONF to the network element resulting in a configuration change.

And if you are intereseted in NETCONF, make sure to check a NETCONF package for ATOM [4] which allows you easily compose and deliver NETCONF commands to the network elements and the Yang-Explorer tool to visually examine YANG models [5]

#Article #Automation #NETCONF #YANG

[1] http://networkop.co.uk/blog/2017/01/25/netconf-intro/
[2] https://ncclient.readthedocs.io/en/latest/
[3] https://github.com/mbj4668/pyang
[4] https://atom.io/packages/atom-netconf
[5] https://hub.docker.com/r/hellt/yangexplorer-docker/

It is always tempting and interesting to see how big guys do their networks. We saw some pieces from Google, Facebook, Amazon, LinkedIn and now Twitter comes. Big 5 is all set!

Last week engineering force at Twitter released an article titled "The Infrastructure Behind Twitter: Scale" [1]. The article starts off with networking field in focus and covers both DC and Backbone challenges Twitter faced over the time.

Data Center story is no surprise at all, IGP started to give more troubles that benefits and was swapped with "BGP as IGP" solution. Classics of modern DC design. By the way, there is a bonus track in the DC section of the article — a nice slide deck explaining how Twitter did this migration on a live network [2].

At the Backbone side Twitter surpisingly had no TE at some point (o.O). Now they most certainly do and they also adopted TE++ from Juniper [3] which helps them overcome bin-packet problem (common problem for Big 5, Facebook had this as well). After all RSVP-TE autobandwith has some serious players that have implemented it.

When it comes to Edge, problems like PoP design and steering traffic to PoPs start to pop out. Serving a customer from a closest point available (less RTT means less delay and more goodput) is a corner stone for worldwide scale players. On the latter case Twitter ditched geo-DNS in favor of BGP-anycast. We saw this done by LinkedIn and Facebook [4],[5]

Though from a birds eye view all the probles are the same we should thank Twitter for sharing! Maybe we'll see more goodnes from their Engineering dept. soon.



#Article #Datacenter #RSVPTE #BGP

[1] https://blog.twitter.com/2017/the-infrastructure-behind-twitter-scale

[2] https://www.nanog.org/sites/default/files/20161016_Woodfield_Routing_Protocol_Migrations_v1.pdf

[3] https://www.juniper.net/documentation/en_US/junos/topics/concept/dynamic-bandwidth-management-overview.html

[4] https://www.youtube.com/watch?v=LPCbKzhvAGc

[5] https://ripe73.ripe.net/archives/video/1433/

Here is the question: if Host A wants to transmit some data across TCP/IP network to Host B with IP address of 1.2.3.4 how will this Dest_IP address be represented?

Correct, it will be hex encoded, but will the bytestream be like 0x01 02 03 04 or 0x04 03 02 01? Yep, you see where I am going, its endianness who is telling us which byte comes first.

So take a look at this short article which is a perfect read on Endianness. It uncovers why x86 CPUs (back in 90-00's) were a bad choice for networking equipment and how the hell Gulliver's Travels has mixed up with all of it?

#Article #TCP

http://barrgroup.com/Embedded-Systems/How-To/Big-Endian-Little-Endian

Hey there, engineers! Its January 1st 2017 and we are happy to welcome you and wish you all the best.
But is it 2017 indeed? How would one tell if his clock is good, if its in sync with the world clock? Yeah, you got it, in the era of the leap second and New Year eve what topic could we bring up if not NTP?

Lucky us, an Australian SRE@Canonical Paul Gear wrote a 5-post long topic called ""The School for Sysadmins Who Can’t Timesync Good and Wanna Learn To Do Other Stuff Good Too"". We bet you'll become grandmaster of NTP once you read all five of them!

#Article #NTP #Synchronization

Part 1 — The problem with NTP: https://libertysys.com.au/2016/09/the-school-for-sysadmins-who-cant-timesync-good-and-wanna-learn-to-do-other-stuff-good-too-part-1-the-problem-with-ntp/

Part 2 — How NTP works: https://libertysys.com.au/2016/10/the-school-for-sysadmins-who-cant-timesync-good-and-wanna-learn-to-do-other-stuff-good-too-part-2-how-ntp-works/

Part 3 — NTP install and configure: https://libertysys.com.au/2016/10/the-school-for-sysadmins-who-cant-timesync-good-and-wanna-learn-to-do-other-stuff-good-too-part-3-ntp-installation-and-configuration/

Part 4 — Monitoring and Troubleshooting: https://libertysys.com.au/2016/10/the-school-for-sysadmins-who-cant-timesync-good-and-wanna-learn-to-do-other-stuff-good-too-part-4-monitoring-troubleshooting/

Part 5 — Myths, misconception and best practices: https://libertysys.com.au/2016/12/the-school-for-sysadmins-who-cant-timesync-good-and-wanna-learn-to-do-other-stuff-good-too-part-5-myths-misconceptions-and-best-practices/

Here is your fresh IPv6 fix: Tenth iNOG, namely iNOG::A, is all about IPv6 experience.
Technical talks are:
1) Orla McGann (HEAnet) An Irish IPv6 Fairytale
2) Nathalie Trenaman (RIPE) The Sad Tale of 462 Operators Who Switched Off IPv6* (*with a happy ending)
3) Ed Horley (Groupware Technology) IPv6 Operating Challenges

Particulary interesting talk was given by Nathalie from RIPE who was talking about IPv6 global perception seen from RIPE point-of-view.

#Video #iNOG #IPv6

https://www.youtube.com/watch?v=WSH6jxmqrag

There is a popular saying that you don't need to be a programmer to automate your network. Might be true, though you definitely won't succeed in automation tasks without basic Regular Expressions knowledge, that you should take for granted.
Sad thing that regular expressions are not an easy nut to crack, and with this post we would like to share with you useful resources that will help you meet and greet RegExps!

#TipsTricks #Programming

http://shop.oreilly.com/product/9780596528126.do -- Mastering Regular Expressions, 3rd Edition.

http://www.regular-expressions.info/tutorial.html -- a free and massive tutorial on RegExps

https://projects.lukehaas.me/regexhub/ -- regexps collection for different tasks

https://regex101.com/ -- the best online regexp engine to test and validate your regexps

https://regexcrossword.com/ -- solving regexps just for fun

https://www.cheatography.com/davechild/cheat-sheets/regular-expressions/ -- book a place on your desk to hang this RE cheatsheet