FujiApple
Joined 7 years ago
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237
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47
Member since
Jun 7
Recent submissions
Comment · 6 months ago
Comment · 1 year ago
I’ve recently been building a similar tool [1] which defines a specification for CLIs, though the goals are slightly different to the tool you mention I think. I just added support for fish as it happens.
Comment · 1 year ago
Something I’ve been working on recently is a command line tool [1] to bring clap declarative command line parsing to shell scripts. Unfinished WIP but largely functional.
Comment · 1 year ago
Great concept. I was on mobile and agree the custom keyboard is far from ideal. As others have said I also found it to be overly US-centric. Keen to see how this develops, feels like a winning idea!
Comment · 1 year ago
You can, with several caveats, detect which hop(s) on the path perform NAT by using some trickery [1]:
> NAT devices are detected by observing a difference in the expected and actual checksum of the UDP packet that is returned as the part of the Original Datagram in the ICMP Time Exceeded message. If they differ then it indicates that a NAT device has modified the packet. This happens because the NAT device must recalculate the UDP checksum after modifying the packet (i.e. translating the source port) and so the checksum in the UDP packet that is nested in the ICMP error may not, depending on the device, match the original checksum.
[1] https://github.com/fujiapple852/trippy/releases/tag/0.11.0
Comment · 2 years ago
OP, you may find this [1] “trick” useful. It allows you to dynamically determine the correct byte order for the various IPv4 headers for the platform and thus avoid the need to statically decide on the byte ordering for each platform you intend to target.
You may also find this [2] table useful, it shows which platforms allow the combination of IPPROTO_ICMP + IP_HDRINCL so it may be used without elevated privileges.
In general, my experience of raw sockets is that they are not very “raw” at all, the OS can and does still perform a variety of modifications and additions to what you send and receive, in highly platform specific and often poorly documented ways. In particular, TCP and raw sockets should generally be avoided.
[1] https://github.com/fujiapple852/trippy/blob/master/crates/tr...
[2] https://github.com/fujiapple852/trippy/issues/101#issuecomme...
Comment · 2 years ago
It’s not guaranteed to be accurate, but tracing using the UDP/dublin strategy with a fixed dest port and varying src port per round can help to identify and visualize valid ECMP flows. I recently wrote some guidance [1] on using Trippy in this way.
[1] https://github.com/fujiapple852/trippy?tab=readme-ov-file#ud...
Comment · 2 years ago
I recently had to look at the implementation of the Sparkline [1] widget in Ratatui which uses a similar Unicode technique but scales nicely for sparklines with larger vertical size.
[1] https://github.com/ratatui/ratatui/blob/20c88aaa5b9eb011a522...
Comment · 2 years ago
Exploring adding the (novel?) concept of forward and backward packet loss heuristics to Trippy [1] as discussed here [2].
Comment · 2 years ago
I recently tried Zulip [1] again after a few years and the UX is much improved on web and mobile, worth a look (it is OSS and you can self host).
Comment · 2 years ago
This Tailscale blog [1] from 2020 has been posted on HN many times before I’m sure but is worth highlighting again as it does a great job outlining the technical complexities that CGNAT (and NAT in general) introduce.
I have my head in this space at the moment as I’m trying to implement NAT detection (as pioneered by Dublin traceroute [2]) into Trippy [3].
[1] https://tailscale.com/blog/how-nat-traversal-works
Comment · 2 years ago
What is the state of the art for running NetBSD (and other *BSD) in CI such as GitHub actions?
Edit: to add a bit more detail, I maintain a cross platform tool [1] on GitHub and require a way to build and test it in CI for several platform not natively supported by GitHub.
Currently I use cargo-cross [2] to build it from a Linux OS but this doesn’t work for running the tests.
One option I’m aware of is running a qemu VM on Linux, which is the approach taken by postgres [3].
Another option is using an external CI provider such as Cirrus who claim to have native support [4] for various *BSD.
[1] https://github.com/fujiapple852/trippy
[2] https://github.com/cross-rs/cross
Comment · 2 years ago
Thanks! I’ll take a look
Comment · 2 years ago
For the RTT and loss% measurements Trippy just does the obvious thing (i.e. RTT = recv time - send time and loss% = lost / total_sent).
There is a plan [0] to add custom columns to Trippy and then to add various jitter measurements [1].
Thanks for pointing out the above RFCs, I'll take a look at those and see if they make sense to add to Trippy.
Trippy now includes [0] forward loss (Floss) and backward loss (Bloss) _heuristics_ to help surface such behaviour.
The idea was inspired by our previous discussion [1] on the topic on HN some time ago!
These columns are experimental and so not shown by default but can be enabled [2].
[0] https://github.com/fujiapple852/trippy/blob/master/RELEASES....
[1] https://news.ycombinator.com/item?id=38591827
[2] https://trippy.rs/reference/column