The only way I know how to get into thuban2 is to be on canopus or mirzam, and from there,
ssh thuban2
To do important stuff, one needs to have root (aka superuser) privileges.
I tried sudo blah blah blah with limited results.
Bruce says I need instead to do
sudo su – (that’s a blank followed by a minus sign)
see also my entry for location of backups on canopus
e.g. /var/share/data/psrdata
and /var/share/home/jweisber
(note that when I first log in to thuban2, I go to a wrong /home jweisber )
–joel 20220804
(But not so fast for mirzam’s /usr/share/astro/ “real” location on thuban2:
when I did a “mount” command on mirzam on 20231231, I discovered that
/usr/share/astro/ on mirzam is really on thuban2’s /var/share/astro_centos7/ ! )
–joel 20231231
tl;dr: this stems from our upgrade from centos6 to 7. The directory still occupying thuban’s
/var/share/astro/ is a carcass from centos6 days!
A cleaner way to free up firefox cache space, was provided by Mike Tie via Bruce Duffy.
I noticed I couldnt log in to carleton email via astronet firefox and these guys said it was because of a carcass in cache. So this is the procedure for clearing cache, which can also often bring a user’s space down below their quota limit:
Firefox has cached the old info, and now you need to clear the firefox cache. To do that, Launch firefox, click the three bars in the upper right corner of the firefox window, click Preferences, click the lock icon (middle left of the window), scroll down to “Coookies and Site Data”, click on “Clear Data…”, make sure both items are checked, and click “Clear”, and then click “Clear Now”.
One needs to be root or have sudo privileges to do this:
sudo shutdown -rv 2
-rv 2 means :
r is restart after shutdown;
v means verbose
2 means in 2 minutes
on thuban2, go to
/var/share/data/ ≡ /data/psrdata/ on other machines.
/var/share/astro ≡ /usr/share/astro/ on other machines.
Firefox setting for users who’s home dir lives on NFS – Bruce Duffy May 2013
Here’s how to tell Firefox that your homedir is sitting on an NFS filesystem:
This update (10.8) also fixes the following bug:
* In certain environments, storing personal Firefox configuration files
(~/.mozilla/) on an NFS share, such as when your home directory is on a
NFS share, led to Firefox functioning incorrectly, for example, navigation
buttons not working as expected, and bookmarks not saving. This update
adds a new configuration option, storage.nfs_filesystem, that can be used
to resolve this issue.
If you experience this issue:
1) Start Firefox.
2) Type “about:config” (without quotes) into the URL bar and press the
Enter key.
3) If prompted with “This might void your warranty!”, click the “I’ll be
careful, I promise!” button.
4) Right-click in the Preference Name list. In the menu that opens, select
New -> Boolean.
5) Type “storage.nfs_filesystem” (without quotes) for the preference name
and then click the OK button.
6) Select “true” for the boolean value and then press the OK button.
(BZ#809571, BZ#816234)
All Firefox users should upgrade to these updated packages, which contain
Firefox version 10.0.8 ESR, which corrects these issues. After installing
the update, Firefox must be restarted for the changes to take effect.
Bruce installed the gv package for viewing and printing postscript. It works great for viewing. For printing, it has problems. Bruce developed this workaround (with a few mods by Joel):
‘gv’ uses the ‘lpr’ command, and if a printer as set as the default in CUPS it will use that printer automatically. You can hear the printer warm up, but nothing comes out of the printer.
Fortunately ‘gv’ is packaged with a set of file conversion utilities,
including ‘ps2pdf’. On the command line you can issue this command:
# ps2pdf xxx.ps – | lpr
and that will convert the ps file to pdf (version 1.4) before sending it to lpr. (You can also convert in place – ie turn your postscript file into a pdf on disk with ps2pdf, and then send the pdf to the printer whenever you want.)
To print a ps on the fly, though:
gv’s print command dialog window has a typein labeled ‘print command’
and it’s automagically populated with the string ‘lpr’. However you
can change that string to ‘ps2pdf %s – | lpr’. You can also change
the default print string from ‘lpr’ to whatever you want in
GhostScript options, but that would break printing of non .ps Here’s.
To change the default print string in ‘gv’, select:
State->Setup Options
… Look for the Print Command field, and change the value from
‘lpr’ to ‘ps2pdf %s – | lpr’ (w/o the single quotes).
The change is saved to ~/.gv as the line:
GV.printCommand: ps2pdf %s – | lpr
–bruce via joel
Newest update 2024 Aug to reflect that backups are have been stored on canopus: for several years:
Go to canopus:/thuban2-backups
Bruce has an automatic (cron) job do a weekly backup of thuban onto canopus.
On canopus,
df -h gives the various mount points, incl
“Filesustem” /dev/mapper/centos_canopis-thuban2–backups”\
” Mounted on” /thuban2/backups
Navigate down to whatever file you’re looknig for, and copy over to a safe place (Careful: do not overwrite newer file of same name on thuban!)
See also post on root superuser privileges on thuban2 (although current post you are reading deals with canopus, which is where weekly backups are stored).
–joel
control-alt-backspace logs you out