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Comment by pas | Hacker News Reader

to get the gateway: ip route show default

> > ifconfig's output is simply more readable IMO

I prefer iproute2's terseness.

I'm not sure "terse" is the right adjective. It presents basically the same amount of information as ifconfig (minus the packet counters) and actually adds a few more flags. It's all about the formatting really. Simply adding an empty line between each interface would go a long way. Also starting the line with the interface name instead of the index.

Adding more punctuation to delimit the fields (, : etc...) would be nice too. I mean what the hell:

    mtu 1500 qdisc pfifo_fast qlen 1000

So glad I'm not the only one with the same criticisms

I think the problem is, that these tools lack the extended human friendly output. They work well for those who use them regularly, but there's no `ip --explain`. Alas Linux and the kernel is famous for having very barebones or bloated and useless documentation.

It sounds a little bit like air traffic control: "roger dev gbe zero niner alpha one you are cleared for proto kernel scope link strip 4 dash 7 F L 11400 gamma zulu src please copy."

I can take "mtu 1500" part, and sort-of "qdisc", but what's up with repeating obscure parameters at their default values, for each and IP address:

  valid_lft forever preferred_lft forever

Those are lifetimes for default (outgoing) address selection.

RFC 3484 "Default Address Selection for Internet Protocol version 6 (IPv6)".

Huh, does "ip" also support "tc" (traffic control) commands - qdisc is a queueing discipline... tc seems to be the an earlier thing from the people who brought us ip. tc must have the worst command line interface and documentation ever - it is very hard and very frustrating to use, like no other command line interface I've ever seen.

I once tried to use tc and gave up after more than a day of trying, that is how bad it is. The syntax is a word soup and the semantics are very poorly explained.

ip/ss/tc are all netfilter based things all in the iproute2 repo.

http://inai.de/images/nf-packet-flow.png

tc is implemented by packet pacing at either egress or ingress steps.

and this is how iproute2 compares to the old net-tools stuff: https://linoxide.com/wp-content/uploads/2014/05/Linux-Nettoo...

netfilter: https://en.wikipedia.org/wiki/Netfilter#/media/File:Netfilte...

regarding UI/UX/CLI. yes, there's no arguing about it, it's just horrible. no documentation, no discoverability, no sanity. but it works, and it's free :o

I spent a bit too long on playing with tc a while ago. The best I could get it was to limit each person's download speeds from the one internet connection we had.

I'm with you on tc having the worst interface and documentation that I have seen from a command before. I spent maybe a few days total on it then gave up because I figured if there isn't much documentation on it, it isn't worth figuring out.

I used tc for something interesting once: I setup Cassandra nodes in distinct docker containers running on a single laptop. I installed tc in each container to throttle packets flowing between containers and in so doing, simulated a lossy, high latency WAN network. The goal was to evaluate how Cassandra fared as network latencies increased.

tc fit the bill nicely.

Did you remember to disable your swap file/partition?

https://stackoverflow.com/questions/22988824/why-swap-needs-...

MegaCLI (lsi hw raid control) sees your tc and raised you a few million awful flags.

I'm pretty sure MegaCLI was written by someone who used to write software for digital phone switches.

Ah, my old friend MegaCLI. Simultaneously the most verbose and the most useless --help output I've ever seen from a command-line program.

After working with it almost daily for years I'm finally fluent in MegaCLI. I can even understand the --help for the most part. Time to get a new job I guess.

Nah.. Just time to relearn it all with StorCLI instead.

:-(

I see your MegaCLI and raise you certutil: https://docs.microsoft.com/en-us/windows-server/administrati...

Oh fair enough but in the context of Linux command lines I think MegaCLI is genuinely one of the worst UX designs ever. Up until recently (post Balmer), Microsoft didn’t heavily emphasize the CLI for most things so a bad UX is not surprising.

That just shows its user-unfriendliness further. Here's a more readable version of the output:

> ip route | column -t

(With iproute2 4.3.0, I get the same output between "route", "route show", and "route show default"; no idea if it's changed since.)

Wow. That's actually kind of a tiny little brilliant gem that remains to be discovered by many. I, for one, had never though about trying this.

Alas it doesn't work quite so well for "ip addr". It would have been great if they'd just decided on CSV or JSON or whatever and then relied on secondary utilities to go to "pretty-printed".

Somewhere else in here, someone else mentioned that "ip" has "--oneline", which does seem to work decently, at least for the first couple columns:

   ip --oneline addr | column -t

When asking "what's the default gateway?", more often than not, the real question you have is "what's the gateway to IP address X", which would be:

  ip route get X

No it's not, it's usually "What is the default gateway on this network segment because I want to plug my laptop in"

I do use ip route a fair bit - if I have a machine connected to two (or more) network segments and want to ensure traffic gets routed back the way it came

However my main criticism for "ip route" is that it's inconsistent and a change route "route"

"route" does reverse dns lookups - e.g "my.server.tld rather than "1.2.3.4", or "default" rather than "0.0.0.0"

"route -n" shows 1.2.3.4

"ip route" doesn't do reverse lookup, however it does say "default" rather than "0.0.0.0".

Then reask: whats the gateway to 0.0.0.0/0

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