On Sat, Jan 09, 2021 at 11:03:28AM -0600, Thomas Anderson wrote:

I did "pip install twisted" and it seemed to install okay.

Now I'm trying to get https://twistedmatrix.com/documents/current/_downloads/9620a18fe21cabe0de79c... running locally. To do so it says I need to first do "ckeygen -t rsa -f ssh-keys/ssh_host_rsa_key". ssh-keygen is a command that's commonly available on Linux systems but ckeygen... that appears to be a twisted thing. When I try to run that on Ubuntu I get a "-bash: ckeygen: command not found" error.

It's in the Twisted distribution (perhaps pip has installed it to somewhere not on your $PATH? On Linux, hopefully you're using pip in conjunction with a virtualenv, in which case you may need to activate the virtualenv), but you do need to use "pip install 'Twisted[conch]'" to get the right dependencies. $ virtualenv twisted-test $ twisted-test/bin/pip install 'Twisted[conch]' $ twisted-test/bin/ckeygen --help Usage: ckeygen [options] Options: -C, --comment= Provide new comment. -N, --newpass= Provide new passphrase. -P, --pass= Provide old passphrase. -b, --bits= Number of bits in the key to create. -f, --filename= Filename of the key file. --help Display this help and exit. -l, --fingerprint Show fingerprint of key file. --no-passphrase Create the key with no passphrase. -o, --format= Fingerprint format of key file. [default: sha256-base64] -p, --changepass Change passphrase of private key file. --private-key-subtype= OpenSSH private key subtype to write ("PEM" or "v1"). [default: PEM] -q, --quiet Quiet. -t, --type= Specify type of key to create. --version Display Twisted version and exit. -y, --showpub Read private key file and print public key. ckeygen manipulates public/private keys in various ways. Alternatively, if you don't mind having a Twisted version of an age that roughly matches when the Ubuntu version you're running was being prepared, then you can run "sudo apt install python3-twisted" to get a system-installed version. That'll give you /usr/bin/ckeygen3 rather than ckeygen, but close enough. Whether the older version is good enough depends on what you're doing. -- Colin Watson (he/him) [cjwatson@debian.org]