F5 DevCentral
devcentral.f5.com · Company blog · on HN since 2008
F5's DevCentral publishes technical articles on load balancers, iRules scripting in Tcl, proxies, SSL, and web and cloud topics.
What HN saysHN commenters link its iRules article to explain why F5 devices use Tcl, and find BigIP iRules pleasant, though some posts are dated.
42HN people shared it
17linked it in comments
958stories submitted
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Most-shared posts
- 1Dispelling the New SSL Myth2 people · 31 points · first shared 2011 · 38 comments on HN
- 28 things you can do with a proxy2 people · 10 points · first shared 2008 · 1 comments on HN
- 3Cloud Computing: Vertical Scalability is Still Your Problem2 people · 1 points · first shared 2008 · discussion on HN
- 4Irules concepts tcl the how and why2 people · first shared 2019
- 5HttpFox: The FireFox add-on you can't live without1 people · 47 points · first shared 2008 · 13 comments on HN
- 6Being first doesn't mean proprietary - even if it is Microsoft1 people · 26 points · first shared 2009 · 1 comments on HN
- 7Why Flash can't win the Web application war1 people · 18 points · first shared 2008 · 30 comments on HN
- 8We're sorry. The IPv4 address you are trying to reach has been disconnected.1 people · 17 points · first shared 2009 · 8 comments on HN
- 9Booth Babes Don't Wear Glasses1 people · 17 points · first shared 2010 · 36 comments on HN
- 10Taking Down Twitter as Easy as D.N.S1 people · 16 points · first shared 2009 · 5 comments on HN
- 11Google SPDY Protocol Would Require Mass Change in Infrastructure1 people · 13 points · first shared 2009 · 12 comments on HN
- 12Load testing as a service: A Look at Load Impact (Beta)1 people · 12 points · first shared 2009 · 1 comments on HN
- 13Google Wave Choice of XMPP Not the Death of HTTP1 people · 12 points · first shared 2009 · 2 comments on HN
- 14Web Application Security At the Edge is More Efficient Than In the Application1 people · 12 points · first shared 2009 · 4 comments on HN
- 15The worst misuse of the term 'load balancing' ever1 people · 12 points · first shared 2008 · 7 comments on HN
What HN people wrote when they linked it
deaps · 2019-10-28
A pretty good read on tcl - and why the F5 devices use tcl for their iRules (2012, Updated two years ago).
https://devcentral.f5.com/s/articles/irules-concepts-tcl-the-how-and-w…
anonacct37 · 2017-07-26
Not sure if it's lunch has been eaten, but TCL was great for embedding and pretty widely used. So, to mix metaphors, it definitely had a few great meals before losing the spotlight.
I've seen it embedded in load balancers and used for test harnesses for embedded devices.
https://devcentral.f5.com/articles/irules-101-01-introduction-to-irule…
otterley · 2017-04-22
BigIP's iRules (Tcl) are pretty nice. (https://devcentral.f5.com/irules). I hear HAproxy has Lua support now, but I don't know how comprehensive it is compared to iRules.
Also, F5 load balancers have real hardware failover capability, and can even synchronize TCP session state across instances. That's a pretty nice feature.
aeden · 2011-04-24
It's worth pointing out that this article is a bit long in the tooth. Although perhaps biased responses, it's worth looking at some other thoughts on the subject:
http://devcentral.f5.com/weblogs/macvittie/archive/2011/03/21/the-skel…
http://dev.robertmao.com/2007/06/30/global-dns-load-balancing-for-free… (towards the end, and yes, the grammar is bad)
http://blogs.sun.com/davew/entry/thoughts_on_global_server_load
throw0101a · 2021-08-20
> I'm using the acme.sh client but the process will be similar no matter which client you choose to use.
Always nice to see some variety in clients along side the official Let's Encrypt one.
While we do use the official Python-based client at works at times, whenever I install it via apt, and it pulls in a whole bunch of dependencies, it's a bit disconcerting to me.
I'm a bit partial to dehydrated, which is a shell script (works under Bash and Zsh): I find it a lot easier to understand. It's handy to put on Linux/POSIX-based appliances like F5s, where the only prerequisites are Bash, cURL, and OpenSSL (and standard Unix tools like sed, grep, etc):
* https://devcentral.f5.com/s/articles/lets-encrypt-on-a-big-ip
* https://github.com/EquateTechnologies/dehydrated-bigip-ansible
nl · 2021-02-24
I've worked on (non-Atlassian) SSO projects where the provider used the referrer to send the client to the page-after-logout (and occasionally page-after-login) if they weren't set as parameters in some circumstances.
Here's a reference to a F5 device providing SAML SSO services and having a similar issue:
https://www.devcentral.f5.com/s/question/0D51T00007npfjw/chrome-browse…
bch · 2020-06-25
Tcl is (last I knew) still remarkably big on “the edges” of networks: f5/a10 devices (iRules scripting[0]), used to be (is it still?) used for Cisco iOS scripting[1], was used as the glue language for Tealeaf session/network capture[2] (when it was deployed as on-premises installation ), and control language for Argonne National Lab cluster control[3]...
[0] https://devcentral.f5.com/s/articles/irules-concepts-tcl-the-how-and-w…
[1] https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ios_tcl/configuratio…
[2] https://help.goacoustic.com/hc/en-us/articles/360043736414-Passive-Cap…
[3] https://www.mcs.anl.gov/~wozniak/papers/Swift_Tcl_2015.pdf
thr0w__4w4y · 2020-06-21
That looks like a good series to watch, thank you.
Totally unrelated, but the first time I saw that technique with writing on the glass and then flipping the video L-R was about 4 years ago when F5 did a good video introduction on elliptic curve cryptography [0]
They (F5) even wrote up the technical details of their Lightboard [1]
[0] https://youtu.be/dCvB-mhkT0w
[1] https://devcentral.f5.com/s/articles/lightboard-lessons-behind-the-sce…
barbegal · 2018-05-31
As a cynic I would say this is an attempt by Google and Cloudflare to collect DNS data. Why else would they provide this service for free?
Both Google's [1] and Cloudflare's [2] DNS privacy policy prohibits them from storing personally identifiable information or from correlating DNS information with other Google data coming from the same IP/account but it does allow them to store information about which domains are popular, from which locations and from which type of device.
TLS (and therefore HTTPS) provides a very useful fingerprint based on accepted cipher suites, extensions, compression methods...
[1] https://developers.google.com/speed/public-dns/privacy
[2] https://developers.cloudflare.com/1.1.1.1/commitment-to-privacy/privac…
[3] https://devcentral.f5.com/articles/tls-fingerprinting-a-method-for-ide…
tga · 2018-02-10
It's hardware, not software :-)
"The lightboard itself is made up of a heavy duty frame, a 3/8” sheet of low iron glass (commercial name starphire,) and a string of LEDs to wrap the edges of the glass to shoot light inward to make the neon markers pop on camera."
https://devcentral.f5.com/articles/lightboard-lessons-behind-the-scene…
thomashabets2 · 2015-04-30
> Pure garbage.
From your link: "The servers are also
designed to deliver between 10Gbps and 40Gbps of continuous
bandwidth utilization"
So how many terabits per second are you pushing out? Oh… oh you're not? You're not network bound at all? Well then…
And for reference:
https://www.entrust.com/ssl-is-not-computationally-expensive-anymore/
https://devcentral.f5.com/articles/dispelling-the-new-ssl-myth
From 2011
> Google do it because their content is more dynamic
Isn't Youtube SSL?
tszming · 2014-04-16
netcraft shows mint.com is using f5 BigIP, if they terminate SSL using BigIP and should not be affected: https://devcentral.f5.com/articles/openssl-heartbleed-cve-2014-0160#.U…
clauretano · 2013-05-10
Isn't it fun to explain that to provide SSO to Office 365 you effectively need 8+ ADFS servers and a couple of pairs of load balancers (or NLB) spread across at least two data center locations?[1]
At least now dirsync is 64-bit so they've removed the "don't run this on your ADFS server" bit.
[1]https://devcentral.f5.com/blogs/us/big-ip-and-adfs-part-1-ndash-ldquol…
chx1975 · 2011-02-10
The original source is http://devcentral.f5.com/weblogs/macvittie/archive/2011/01/31/dispelli… and it does not disclose this is a company manufacturing SSL accelerators. It also does not mention SNI.
illumin8 · 2010-10-31
1024^3 = 1073741824
2048^3 = 8589934592 / 1024^3 = 8.
It depends on the implementation. Some implementations are more computationally expensive than others.
See: http://devcentral.f5.com/weblogs/macvittie/archive/2010/09/10/f5-frida…
Average of 5x reduction in transactions per second when moving from 1024 bit to 2048 bit keys.
streety · 2008-12-01
liangzan · 2009-01-22
There're many things you can do with a spare linux box. I do keep a few 'project ideas' links just in case I got some spare time on hand.
Home file server with ZFS - http://breden.org.uk/2008/03/02/a-home-fileserver-using-zfs/
Proxy Server - http://devcentral.f5.com/weblogs/macvittie/archive/2008/10/08/8-things…
Map-Reduce fun with Hadoop - http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_(Singl…
Donate bandwidth with a Tor Server - http://ubuntu-tutorials.com/2007/08/31/how-to-run-a-tor-server-donate-…
More good ideas - http://www.dailycupoftech.com/2007/09/17/put-that-old-computer-to-good…
A Dial-In server - http://www.howtoforge.com/linux_dialin_server