Re: [Hampshire] apache redirection problem
On Fri, 2009-08-14 at 04:31 -0700, Peter Alefounder wrote: If I use a web browser to look at a local html or pdf file, is it possible to set things up so that a link to an external web site is redirected to the local file system? I have tried a .htaccess file along these lines: RewriteEngine on Redirect http://external.site.com/filename.html file:///home/pra/abc/filename.html and also RewriteEngine on RedirectMatch http://external\.site\.com file:///home/pra/abc but in all cases I just get the error message external.site.com could not be found. I have tried putting the .htaccess file in /home/pra/abc and in /home/pra/public_html which is the usual place apache would look for local files. I am not sure where it should go in this case. I am using apache 1.3.34-4.1 on Debian 4.0. This is an isolated system with no Internet connection. I think you are confusing apache and your browser. When you give your browser a URL (or is it a URI) the file: http: https: ftp: part tells the browser which protocol to use. When you have file:///home/pra/abc/filename.html then that will work even if apache is not installed on the system. Your browser is just reading local files. If the URL is http://some.site.com/whatever.html the browser will resolve the the IP address of some.site.com then attempt to connect to port 80 at that address. You have no DNS since your not connected to the Internet therefore you will get the error message external.site.com could not be found. Your browser is not going to attempt to talk to your local apache web server unless you can fool it in to thinking external.site.com is really localhost. Regards, Tom. -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
On Saturday 15 August 2009 00:38:07 Chris Dennis wrote: Hello folks I'm planning to use one or more external USB hard drives to backup a headless server running Debian. I'll probably use rsnapshot, with a script that detects for the presence of the right drive. But how can the server tell the user when it is safe to unplug the drive? Or maybe the user should somehow tell the server I want to unplug the drive -- stop using it and unmount it. The user's only way of communicating with the server is by email or possibly via Webmin. Has anyone come up with a cunning plan to deal with this? cheers Chris -- Chris Dennis cgden...@btinternet.com Fordingbridge, Hampshire, UK I would have thought that when your backup script is complete it would be easy enough to add an unmount command and a mail command to the end of the script. Thus the server unmounts the disk and e-mails the user to tell them that it's been removed. Cheers, Tim B. -- OpenPilot - Open-source Marine Chart Plotter Lead Developer http://openpilot.sourceforge.net -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
Chris Dennis wrote: Hello folks I'm planning to use one or more external USB hard drives to backup a headless server running Debian. I'll probably use rsnapshot, with a script that detects for the presence of the right drive. But how can the server tell the user when it is safe to unplug the drive? Or maybe the user should somehow tell the server I want to unplug the drive -- stop using it and unmount it. The user's only way of communicating with the server is by email or possibly via Webmin. Has anyone come up with a cunning plan to deal with this? cheers Chris Have a look at this USB suspend script:- http://elliotli.blogspot.com/2009/01/safely-remove-usb-hard-drive-in-linux.html -- -- Discover Linux - Open Source Solutions to Business and Schools http://discoverlinux.co.uk -- -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
John Cooper wrote: Chris Dennis wrote: Hello folks I'm planning to use one or more external USB hard drives to backup a headless server running Debian. I'll probably use rsnapshot, with a script that detects for the presence of the right drive. But how can the server tell the user when it is safe to unplug the drive? Or maybe the user should somehow tell the server I want to unplug the drive -- stop using it and unmount it. The user's only way of communicating with the server is by email or possibly via Webmin. Has anyone come up with a cunning plan to deal with this? cheers Chris Have a look at this USB suspend script:- http://elliotli.blogspot.com/2009/01/safely-remove-usb-hard-drive-in-linux.html I use autofs for things like usb firewire drives on our backup server (uses rsync). I've set it up so the drive is unmounted after 30 secs if it's not in use so this might help http://www.autofs.org/ It's also good for things like smb mounts Brian The views expressed here are my own and not necessarily the views of Portsmouth College -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
John Cooper wrote: Chris Dennis wrote: Hello folks I'm planning to use one or more external USB hard drives to backup a headless server running Debian. I'll probably use rsnapshot, with a script that detects for the presence of the right drive. But how can the server tell the user when it is safe to unplug the drive? Or maybe the user should somehow tell the server I want to unplug the drive -- stop using it and unmount it. The user's only way of communicating with the server is by email or possibly via Webmin. Has anyone come up with a cunning plan to deal with this? cheers Chris Thanks for the various replies. The simple unmount after backup idea won't work for me because I'm planning to run rsnapshot via cron every hour while the drive is plugged in, but allow the drive to be taken off-site at weekends or whenever. In fact I think Webmin (for all its faults) will allow the user to unmount the drive and/or see whether it is currently mounted. They can then remove the drive knowing that it will not be used again until the appointed cron time -- 15 minutes past the hour for example. Have a look at this USB suspend script:- http://elliotli.blogspot.com/2009/01/safely-remove-usb-hard-drive-in-linux.html That all looks very elaborate. Is it really necessary? Does this mean that good old 'umount' hasn't been working for USB drives all this time? cheers Chris -- Chris Dennis cgden...@btinternet.com Fordingbridge, Hampshire, UK -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
Chris Dennis wrote: John Cooper wrote: Have a look at this USB suspend script:- http://elliotli.blogspot.com/2009/01/safely-remove-usb-hard-drive-in-linux.html That all looks very elaborate. Is it really necessary? Does this mean that good old 'umount' hasn't been working for USB drives all this time? cheers Chris No, umount works fine, but adding the suspend will tell you the drive can be safely unplugged i.e. all writes have actually finished when umount completes and it is then suspended. On a USB stick the light will go out (this is what windows does). -- -- Discover Linux - Open Source Solutions to Business and Schools http://discoverlinux.co.uk -- -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --
Re: [Hampshire] Safely unmounting a server's external hard drive
Chris Dennis wrote:
John Cooper wrote:
Chris Dennis wrote:
Hello folks
I'm planning to use one or more external USB hard drives to backup a
headless server running Debian. I'll probably use rsnapshot, with a
script that detects for the presence of the right drive.
But how can the server tell the user when it is safe to unplug the
drive? Or maybe the user should somehow tell the server I want to
unplug the drive -- stop using it and unmount it.
The user's only way of communicating with the server is by email or
possibly via Webmin.
Has anyone come up with a cunning plan to deal with this?
cheers
Chris
Thanks for the various replies.
The simple unmount after backup idea won't work for me because I'm
planning to run rsnapshot via cron every hour while the drive is plugged
in, but allow the drive to be taken off-site at weekends or whenever.
In fact I think Webmin (for all its faults) will allow the user to
unmount the drive and/or see whether it is currently mounted. They can
then remove the drive knowing that it will not be used again until the
appointed cron time -- 15 minutes past the hour for example.
Have a look at this USB suspend script:-
http://elliotli.blogspot.com/2009/01/safely-remove-usb-hard-drive-in-linux.html
That all looks very elaborate. Is it really necessary? Does this mean
that good old 'umount' hasn't been working for USB drives all this time?
cheers
Chris
Updated the script to check if hdparm works with the device and fixed
some other errors.
Example run on a USB stick with 2 partitions,/dev/sdc1 and /dev/sdc2
(see mount output after inserting USB device) :-
sudo ./usbsuspend /dev/sdc ( or su -c './usbsuspend /dev/sdc' )
Unmount device partitions (1 to 9)
Found device /devices/pci:00/:00:02.1/usb1/1-4 associated to
/dev/sdc; USB bus id is 1-4
flush all buffers: sync
Syncing device /dev/sdc
drive state is: unknown
Drive does not support sleep mode, skipping hdparm
Unbinding device 1-4
Checking whether /devices/pci:00/:00:02.1/usb1/1-4 can be suspended
Suspending /devices/pci:00/:00:02.1/usb1/1-4 by writing to
/sys/devices/pci:00/:00:02.1/usb1/1-4/power/level
Completed
Script, cut and paste into file called usbsuspend :-
CUT START -
#!/bin/bash
#
# usbsuspend
#
usage()
{
catEOF
usbsuspend
This script is designed to properly put an USB device into suspend
mode that can then be unplugged safely. It sends a SYNCHRONIZE CACHE
command followed by a START-STOP command (if the device supports it),
unbinds the device from the driver and then suspends the USB
port. After that you can disconnect your USB device safely.
usage:
$0 [options] dev
Example:
$0 /dev/sdc
options:
-l show the device and USB bus ID only
-h print this usage
EOF
}
set -e -u
SHOW_DEVICE_ONLY=0
while getopts vlh opt; do
case $opt in
h)
usage
exit 2
;;
l)
SHOW_DEVICE_ONLY=1
;;
?)
echo
usage
exit 2
;;
esac
done
DEV_NAME=${!OPTIND:-}
if [ -z ${DEV_NAME} ]; then
usage
exit 2
fi
echo Unmount device partitions (1 to 9)
umount ${DEV_NAME}[1-9]
if mount | grep ^${DEV_NAME}[[:digit:]]* ; then
12 echo
12 echo the above disk or partition is still mounted, can't
suspend device
12 echo unmount it first using umount (may need to be root)
exit 1
fi
DEVICE=$(udevadm info --query=path --name=${DEV_NAME} --attribute-walk \
| egrep looking at parent device | head -1 | sed -e s/.*looking at \
parent device '\(\/devices\/.*\)\/.*\/host.*/\1/g)
if [ -z $DEVICE ]; then
12 echo cannot find appropriate parent USB/Firewire device,
12 echo perhaps ${DEV_NAME} is not an USB/Firewire device?
exit 1
fi
DEV_BUS_ID=${DEVICE##*/}
echo Found device $DEVICE associated to $DEV_NAME; USB bus id is
$DEV_BUS_ID
if [ ${SHOW_DEVICE_ONLY} -eq 1 ]; then
echo Device: ${DEVICE}
echo Bus ID: ${DEV_BUS_ID}
exit 0
fi
echo flush all buffers: sync
sync
sync
# root check
if [ `id -u` -ne 0 ]
then
echo NOT root, required for hdparm to put drive into sleep and
unbind
exit
fi
echo Syncing device $DEV_NAME
hdparm -C $DEV_NAME 2 /dev/null | grep drive state is: unknown
if [ $? -eq 0 ]
then
echo Drive does not support sleep mode, skipping hdparm
else
hdparm -f $DEV_NAME /dev/null || true
hdparm -Y $DEV_NAME /dev/null
fi
echo Unbinding device $DEV_BUS_ID
if [[ ${DEV_BUS_ID} == fw* ]]
then
echo -n ${DEV_BUS_ID} /sys/bus/firewire/drivers/sbp2/unbind
else
echo -n ${DEV_BUS_ID} /sys/bus/usb/drivers/usb/unbind
echo Checking whether $DEVICE can be suspended
POWER_LEVEL_FILE=/sys${DEVICE}/power/level
if [ ! -f $POWER_LEVEL_FILE ]; then
12 catEOF
It's safe to remove the USB device now but better can be done. The
power level control file $POWER_LEVEL_FILE
doesn't exist on the
