Adam Chappell @packetsource

Packet network technology enthusiast: Internet, security, BGP, automation/programmability. GTT AS3257. Ham M0IPX, OK8CHP. 8-bit ZX fan. Author, blogger, writer. blog.packetsource.net London, England; Prague, Czech Joined November 2010

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Adam Chappell @packetsource

a month ago

I want to believe that there exists a draft of this post with the slug, Transparent Route Servers considered harmful! blog.cloudflare.com/enforce-first-…

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Adam Chappell @packetsource

a month ago

The Cloudflare folks investigating the stubborn issue of first AS verification in BGP AS_PATH attributes, and the surprising difference in default behaviour between JUNOS rpd (stemming from original gated behaviour?) and Cisco IOS. Perhaps it calls for an RFC8212 hot-fix.

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Adam Chappell @packetsource

2 months ago

@DireStraits77 Goodness me, I will never complain about Knopfler’s singing again! 😊

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Adam Chappell @packetsource

3 months ago

@LundukeJournal Herculean public service effort here that will pay dividends I am sure

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Adam Chappell @packetsource

4 months ago

@NetworkQueenX I think the real root (sorry!) of STP issues is the instinctive reaction most of us have to turn something complicated off in order to to reduce the complexity domain of something we are dealing. This serves well for most problems, but it’s a disaster for loop-free networking.

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Adam Chappell @packetsource

6 months ago

If stimulating the grey cells is one of your new year resolutions this year, add a linguistic dimension with “Learning Russian Verbs” from @chrispinnock. Get it in January and you may be пла́ча (crying, with happiness hopefully) at the discount!

Chris Pinnock | drchris.tez @chrispinnock

6 months ago

📚 I'm offering a $3 discount on my book Learning Russian Verbs for the rest of January on @leanpub. 💸Use this link to purchase (regular price $12.50; discounted price $9.50): leanpub.com/learningrussia… 👉 Learn the basics of Russian verb grammar and learn 133 common verbs,

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Adam Chappell @packetsource

6 months ago

Forget Kandy Krush, Replicube or other word game brain teasers. Juniper/HP have nailed it with their innovative puzzle games! Get that cognitive workout you need with the Juniper Port Checker and see if you can load your box correctly! I can't get past the MX304 level...!

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Adam Chappell @packetsource

7 months ago

@anurag_bhatia Yes MED comparison scoped to neighbor AS is disabled at GTT/3257 (“always-compare-med”) which exacerbates this effect I think. Certainly allows a freer fight on IGP distance between different peer routes

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Adam Chappell @packetsource

7 months ago

@timClicks @ZacharyIndy Highlights for me, Tim - Rust’s unsafe is not unsafe! 5m30 - Runtime checks still mean a crash (just as in Rust). 4m30 But crucially, give @filpizlo Mr Pizlo his due. Fil-C is an incredible innovation on plain-old C.

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Adam Chappell @packetsource

8 months ago

From scratch Linux-compatible (userland ABI) kernel for Aarch64, making use of Rust’s async/.await model in order to reduce kernel stack usage to one-per-CPU core (rather than one per kernel task) github.com/hexagonal-sun/…

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Adam Chappell @packetsource

8 months ago

Java once boasted of “write once, run everywhere,” which was quickly bastardised to “debug everywhere”. But the Cloudflare folks seem to have managed to earn the “debugged by everyone” accolade for @eastdakota’s unfortunate unwrap()

Oscar Franco @ospfranco

8 months ago

I'm amazed that the whole cloudfare outage happened because of an unwrap() The beauty of Rusts Result monad is that it literally tells you that operations can fail. Anyone with a bit of experience on production knows that everything that can fail WILL fail... The only time I

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Adam Chappell @packetsource

8 months ago

Probably easy to criticise the Cloudflare team for using such a construct in production, but I think what we can admire is the rapid diagnostic and reporting effort that must have occurred to get the level of transparent reporting we see, even if it reveals some embarrassments

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Adam Chappell @packetsource

8 months ago

For the uninitiated, Rust's unwrap() is a brute-force "open and use this value" function for use on variables that might be error values or nullable. It's designed for use when any error condition is absolutely fatal and a program abort should be the consequence.

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Adam Chappell @packetsource

8 months ago

Oh no! Major blow for Rust advocates and afficianados everywhere as Matt Prince @eastdakota reveals a stray unwrap() in Cloudflare’s shiny new FL2 rust code was responsible for yesterday’s quick trip back to books by candlelight!

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Adam Chappell @packetsource

8 months ago

youtu.be/oTpA5jt1g60?si…

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Adam Chappell @packetsource

8 months ago

Taskman Dave @davepl1968, on the trouble with Windows and why Microsoft should ship a low-friction, predictable, deterministic manual transmission edition as a daily driver for power users who just need to get stuff done with least astonishment and exasperation

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Adam Chappell @packetsource

10 months ago

@artofneteng I think we should have done expanded communities to complement extended communities, homage to DOS!

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Adam Chappell @packetsource

10 months ago

@artofneteng Swap large and extended here as I recall. Large has the Subject:Object:Verb structure, each field 32 bits. Extended (which preceded Large) is vari-format (64 bits). Extended gets used in VPN for instance with Route Targets, which themselves have three formats, aaargh

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Adam Chappell @packetsource

10 months ago

@stubarea51 Heasley’s shrubbery.net branch of the original Cisco reference implementation, tac_plus, might be worth looking at. shrubbery.net/tac_plus/