2016-12-08 Cider Woes

I’m trying to get Cider to work on my laptop running OSX and failing. This makes me unhappy because I managed to do it on a Windows machine with lots of Cygwin so I felt that getting it to work on a Mac should be a breeze.

Basically, what I have set up my little project using lein and can run it from the command line and from eshell, and I use Clojure Mode, but when I run M-x cider-jack-in I see is this in my *Messages* buffer:

Starting nREPL server via /Users/alex/bin/lein update-in :dependencies conj \[org.clojure/tools.nrepl\ \"0.2.12\"\ \:exclusions\ \[org.clojure/clojure\]\] -- update-in :plugins conj \[cider/cider-nrepl\ \"0.15.0-SNAPSHOT\"\] -- repl :headless...
Mark set
nREPL server started on 53929
[nREPL] Establishing direct connection to localhost:53929 ...
error in process filter: nrepl--direct-connect: [nREPL] Direct connection failed
error in process filter: [nREPL] Direct connection failed

But now I have three buffers named *nrepl-server ... with contents such as nREPL server started on port 53872 on host 127.0.0.1 - nrepl://127.0.0.1:53872.

This reminds me... My Mac keeps deleting my /etc/hosts file which means that localhost is borked:

$ ping localhost
ping: cannot resolve localhost: Unknown host

So I added it back to /etc/hosts.

127.0.0.1 localhost

Then I killed the three nrepl-server buffers and tried C-c M-j again.

And it works. Phew!

Sometimes writing these posts just helps me focus as I’m troubleshooting.

​#Clojure ​#Emacs

Comments

(Please contact me if you want to remove your comment.)

⁂

Your mac deleting _etc_hosts file sounds really bad

– nickf 2016-12-08 22:53 UTC

Yeah. I think it rewrites the file whenever the system updates? So any code that depends on localhost mapping to 127.0.0.1 usually breaks after an update. Gah!

– Alex Schroeder 2016-12-08 22:59 UTC

Hi Alex, that deletion of _etc_hosts sounds vary odd. I use emacs, cider, lein etc almost daily on OSX and have not run itno that issue ever. I do use hombrew for emacs and lein. I am now running macOSSierra, but have been doing clojure et. al. on a Macbook for the past few years and used the last2 or 3 OSX versions.

– Tim X 2016-12-09 08:30 UTC

Strange. I also have OpenVPN installed on the Mac and it puts stuff into the file. Googling for the problem shows that some versions of a Cisco VPN used to do the same. I should just deinstall it and see whether that resolves it.

– AlexSchroeder 2016-12-09 11:47 UTC