Some KTH computer tips
Table of Contents
Some notes on getting/sending mail with gnus
Gnus + kth + ssh-tunnelled-sendmail = true
The best way so far seems to be to use SSH-tunnelled sendmail (with kerbererized SSH, of course). E.g., first run
mkdir -p ~/share/bin cd ~/share/bin wget http://www.slac.com/~mpilone/projects/kde/kmailssh/sshsendmail.sh
and then put this into your ~/.emacs:
(setq sendmail-program "~/share/bin/sshsendmail.sh")
and you should be set.
Why is this better? Well, if you're travelling and send email via smtp at smtp.kth.se (rather than sendmail from one of the KTH computers), headers saying "Received from: blabla" will be appended, and this can make various spam filters classify your sent messages as spam (if blabla happens to be a black listed ISP.) This actually happened to me.
Gnus + kth + smtp = true
Note: even better than this is to use SSH-tunnelled sendmail, see above.
How to get gnus to send mail (say from a laptop) via KTH's smtp server: put the following in ~/.gnus and make sure you have gnutls installed. I suppose you'd better replace "your-user-name" below with, well, your user name.
(setq message-send-mail-function 'smtpmail-send-it smtpmail-starttls-credentials '(("smtp.kth.se" 587 nil nil)) smtpmail-auth-credentials '(("smtp.kth.se" 587 "your-user-name@math.kth.se" nil)) smtpmail-smtp-server "smtp.kth.se" smtpmail-smtp-service 587) (setq starttls-gnutls-program "gnutls-cli")
Gnus + kth + imap + kerberos = true
On Ubuntu (it probably works on Debian too), the following will install the program imtest with GSSAPI capabilities:
apt-get install cyrus-clients-2.2 apt-get install libsasl2-modules-gssapi-heimdal
You can now put the following in your ~/.gnus:
(setq gnus-select-method '(nnnil)) ; It is hard to believe, but KTH ; no longer has a news server! (setq gnus-secondary-select-methods '((nnimap "KTH" (nnimap-address "mail1.kth.se") (nnimap-stream gssapi) (nnimap-authenticator gssapi) )))
Gnus + kth + imap = true
Note: GSSAPI/Kerberos is a better solution (see above); with it you will not have to retype your password as often.
Put this into your ~/.gnus:
(setq gnus-select-method '(nnnil)) ; It is hard to believe, but KTH ; no longer has a news server! (setq gnus-secondary-select-methods '((nnimap "KTH" (nnimap-address "mail1.kth.se") (nnimap-stream ssl) ;(nnir-search-engine imap) ; uncomment if you have nnir installed )))
Note: you might want to keep your old select method so that you still can read your nnfolder/nnml mail.
Using gssapi (kerberos) with ssh
How do I avoid typing my password so often?
Put this into your ~/.ssh/config
GSSAPIAuthentication yes GSSAPIDelegateCredentials yes
To get tickets, type
kauth -f --no-addresses
Searching your imap mail via gnus
Install nnir and uncomment the "nnir-search-engine imap"-line above. Alternatively, consider using thunderbird to sift through your inbox.
Html tips for writing home pages
Don't! Use Org mode instead.
Find all ssh fingerprints on server
On the server, run:
ls /etc/ssh/*.pub| xargs -n 1 ssh-keygen -lf # Newer sshd uses the SHA256 hash. In case your client reports # the md5 hash, use: ls /etc/ssh/*.pub| xargs -n 1 ssh-keygen -E md5 -lf
Some network tips and tricks
Find stuff on home network
nmap -sP 192.168.0.1/24
or, use arp:
arp -a
check open ports
sudo netstat -tunlp ahost.math.kth.se
Sound hangs on ubuntu
To restart, run:
pulseaudio -k && sudo alsa force-reload
or possibly
pulseaudio --kill sudo alsa force-reload pulseaudio --start
Other things to try is "pulseaudio –kill", then rm -r ~/.pulse (or ~/.config/pulse) and restarting.
If
sudo aplay /usr/share/sounds/alsa/Front_Center.wav
make sound, but user mode aplay does not, try:
aplay -D sysdefault:CARD=PCH /usr/share/sounds/alsa/Front_Center.wav
Sometime master volume is muted, fix:
amixer -D pulse set Master 1+ unmute
power off external usb disk drive
Run:
udisksctl power-off -b /dev/sdX