Ben Cartwright-Cox
@benjojo.bsky.social
This account is write only! It's selected reposting from my fediverse @[email protected]
Replies are likely not going to be seen!
Replies are likely not going to be seen!
New Blog!
There is lots of RFC1918 space out there, yet most people use the same 10 /24 subnets
I ended up having my OOB LAN collide with someone's home network a few weeks ago, and decided to find a new subnet to use that won't collide backed up with actual usage data!
There is lots of RFC1918 space out there, yet most people use the same 10 /24 subnets
I ended up having my OOB LAN collide with someone's home network a few weeks ago, and decided to find a new subnet to use that won't collide backed up with actual usage data!
Picking uncontested private IP subnets with usage data
blog.benjojo.co.uk
June 5, 2025 at 10:40 AM
New Blog!
There is lots of RFC1918 space out there, yet most people use the same 10 /24 subnets
I ended up having my OOB LAN collide with someone's home network a few weeks ago, and decided to find a new subnet to use that won't collide backed up with actual usage data!
There is lots of RFC1918 space out there, yet most people use the same 10 /24 subnets
I ended up having my OOB LAN collide with someone's home network a few weeks ago, and decided to find a new subnet to use that won't collide backed up with actual usage data!
On May 20th 2025 a BGP message was propagated that triggered some surprisingly disruptive behaviours with two major BGP implementations make up a lot of the internet.
In a new blog post, I will dissect what that message was, and my thoughts on how it happened:
blog.benjojo.co.uk/post/bgp-att...
In a new blog post, I will dissect what that message was, and my thoughts on how it happened:
blog.benjojo.co.uk/post/bgp-att...
BGP handling bug causes widespread internet routing instability
blog.benjojo.co.uk
May 27, 2025 at 11:03 AM
On May 20th 2025 a BGP message was propagated that triggered some surprisingly disruptive behaviours with two major BGP implementations make up a lot of the internet.
In a new blog post, I will dissect what that message was, and my thoughts on how it happened:
blog.benjojo.co.uk/post/bgp-att...
In a new blog post, I will dissect what that message was, and my thoughts on how it happened:
blog.benjojo.co.uk/post/bgp-att...
Reposted by Ben Cartwright-Cox
After sitting on the decision for quite a while, bgp.tools will be switching away from posting updates on X.
Users can follow this account, or the fedi account @[email protected] instead
Users can follow this account, or the fedi account @[email protected] instead
February 12, 2025 at 5:00 PM
After sitting on the decision for quite a while, bgp.tools will be switching away from posting updates on X.
Users can follow this account, or the fedi account @[email protected] instead
Users can follow this account, or the fedi account @[email protected] instead
New blog post!
Ever wondered about the process that grants RFC numbers for documents? Well, worry no more, introducing:
--
The “simple” 38 step journey to getting an RFC
blog.benjojo.co.uk/post/rfc-in-...
Ever wondered about the process that grants RFC numbers for documents? Well, worry no more, introducing:
--
The “simple” 38 step journey to getting an RFC
blog.benjojo.co.uk/post/rfc-in-...
The "simple" 38 step journey to getting an RFC
blog.benjojo.co.uk
December 5, 2024 at 11:02 AM
New blog post!
Ever wondered about the process that grants RFC numbers for documents? Well, worry no more, introducing:
--
The “simple” 38 step journey to getting an RFC
blog.benjojo.co.uk/post/rfc-in-...
Ever wondered about the process that grants RFC numbers for documents? Well, worry no more, introducing:
--
The “simple” 38 step journey to getting an RFC
blog.benjojo.co.uk/post/rfc-in-...
Much like sisyphus is forced to roll a boulder up a hill for eternity, I am now getting payback for buying cheap QLC SSDs that I am seemingly vaporising at the moment
January 22, 2024 at 10:09 PM
Much like sisyphus is forced to roll a boulder up a hill for eternity, I am now getting payback for buying cheap QLC SSDs that I am seemingly vaporising at the moment
It has been 0 days since someones Apple webcam "Reaction Effects" have triggered on a serious biz call
January 11, 2024 at 11:01 PM
It has been 0 days since someones Apple webcam "Reaction Effects" have triggered on a serious biz call
I've published a text version of my #37C3 lightning talk!
"The browsers biggest TLS mistake"
https://blog.benjojo.co.uk/post/browsers-biggest-tls-mistake
"The browsers biggest TLS mistake"
https://blog.benjojo.co.uk/post/browsers-biggest-tls-mistake
January 7, 2024 at 5:37 PM
I've published a text version of my #37C3 lightning talk!
"The browsers biggest TLS mistake"
https://blog.benjojo.co.uk/post/browsers-biggest-tls-mistake
"The browsers biggest TLS mistake"
https://blog.benjojo.co.uk/post/browsers-biggest-tls-mistake
Happy xmas, see some of you soon at #37c3
(Bonus cat pic)
(Bonus cat pic)
December 25, 2023 at 3:22 PM
Happy xmas, see some of you soon at #37c3
(Bonus cat pic)
(Bonus cat pic)
I've got a lightning talk/rant coming up at #37C3!
Hope to see you there: https://pretalx.c3voc.de/37c3-lightningtalks/talk/XGML8T/
Hope to see you there: https://pretalx.c3voc.de/37c3-lightningtalks/talk/XGML8T/
December 24, 2023 at 6:35 PM
I've got a lightning talk/rant coming up at #37C3!
Hope to see you there: https://pretalx.c3voc.de/37c3-lightningtalks/talk/XGML8T/
Hope to see you there: https://pretalx.c3voc.de/37c3-lightningtalks/talk/XGML8T/
*bangs hands on table* DATA DATA DATA DATA DATA DATA DAT-
December 19, 2023 at 8:37 PM
*bangs hands on table* DATA DATA DATA DATA DATA DATA DAT-
As far as I can tell where the Grindavík (Iceland) eruption has surfaced, is around 13km (as the crow flies) from one of the larger data centres in Iceland...
Must be some good disaster response emails going around at the moment!
Must be some good disaster response emails going around at the moment!
December 19, 2023 at 12:20 AM
As far as I can tell where the Grindavík (Iceland) eruption has surfaced, is around 13km (as the crow flies) from one of the larger data centres in Iceland...
Must be some good disaster response emails going around at the moment!
Must be some good disaster response emails going around at the moment!
Looks like Hetzner (24940) typo'd a BGP prepend (2490) when doing traffic engineering towards CoreBackBone (33891).
Woops. It makes it look like Raytheon are upstreams when they are not!
https://bgp.tools/prefix/95.216.0.0/16#connectivity
Woops. It makes it look like Raytheon are upstreams when they are not!
https://bgp.tools/prefix/95.216.0.0/16#connectivity
December 14, 2023 at 2:12 PM
Looks like Hetzner (24940) typo'd a BGP prepend (2490) when doing traffic engineering towards CoreBackBone (33891).
Woops. It makes it look like Raytheon are upstreams when they are not!
https://bgp.tools/prefix/95.216.0.0/16#connectivity
Woops. It makes it look like Raytheon are upstreams when they are not!
https://bgp.tools/prefix/95.216.0.0/16#connectivity
Finally got Office XP working, Look at this! WordArt never got better than this
December 14, 2023 at 12:42 AM
Finally got Office XP working, Look at this! WordArt never got better than this
Say hi to datacenter car park fox who was taking a break from the rain.
December 12, 2023 at 5:53 PM
Say hi to datacenter car park fox who was taking a break from the rain.
I like big cables and I cannot lie
December 12, 2023 at 4:30 PM
I like big cables and I cannot lie
Hm, so a small DLR station takes "only" 25kW to run, based on this emergency generator readout
December 12, 2023 at 11:13 AM
Hm, so a small DLR station takes "only" 25kW to run, based on this emergency generator readout
We are so close to 1.7B Unix epoch
November 13, 2023 at 2:18 PM
We are so close to 1.7B Unix epoch
For some reason the Ceph dashboard is like a fish tank, I literally just keep staring at it.
Especially right now as it's doing a transfer from the old storage machine to the new setup (for bgp.tools)
Especially right now as it's doing a transfer from the old storage machine to the new setup (for bgp.tools)
November 10, 2023 at 10:56 AM
For some reason the Ceph dashboard is like a fish tank, I literally just keep staring at it.
Especially right now as it's doing a transfer from the old storage machine to the new setup (for bgp.tools)
Especially right now as it's doing a transfer from the old storage machine to the new setup (for bgp.tools)
Ooooh, the 0th longitude laser is very visible tonight in London
November 10, 2023 at 10:56 AM
Ooooh, the 0th longitude laser is very visible tonight in London
My NANOG 89 talk on the internal operations of bgp.tools is up on youtube!
https://www.youtube.com/watch?v=83NJllv0q9U
https://www.youtube.com/watch?v=83NJllv0q9U
October 24, 2023 at 6:35 PM
My NANOG 89 talk on the internal operations of bgp.tools is up on youtube!
https://www.youtube.com/watch?v=83NJllv0q9U
https://www.youtube.com/watch?v=83NJllv0q9U
My NANOG 89 version of my "Discovering flaws in BGP error handling" talk is now up on youtube!
https://www.youtube.com/watch?v=-_VBehyNwqg
https://www.youtube.com/watch?v=-_VBehyNwqg
October 24, 2023 at 6:35 PM
My NANOG 89 version of my "Discovering flaws in BGP error handling" talk is now up on youtube!
https://www.youtube.com/watch?v=-_VBehyNwqg
https://www.youtube.com/watch?v=-_VBehyNwqg
Graph improvements to bgp.tools!
On the bgp.tools BGP propagation graphs there are now names attached to the network boxes to help faster comprehension.
In addition, font profiles for the graphs have been normalised between Linux/Windows/Mac
On the bgp.tools BGP propagation graphs there are now names attached to the network boxes to help faster comprehension.
In addition, font profiles for the graphs have been normalised between Linux/Windows/Mac
October 23, 2023 at 11:13 AM
Graph improvements to bgp.tools!
On the bgp.tools BGP propagation graphs there are now names attached to the network boxes to help faster comprehension.
In addition, font profiles for the graphs have been normalised between Linux/Windows/Mac
On the bgp.tools BGP propagation graphs there are now names attached to the network boxes to help faster comprehension.
In addition, font profiles for the graphs have been normalised between Linux/Windows/Mac
Google maps appears to think I can walk on water?
October 20, 2023 at 4:46 AM
Google maps appears to think I can walk on water?
Finally a interface perfect for the gentoo users out there
October 20, 2023 at 12:51 AM
Finally a interface perfect for the gentoo users out there