Why search yourself, though? perldoc’s -f switch searches perlfunc for you, presenting only the documentation for the named operator. Type instead:
$ perldoc -f substr
Tag Archives: linux command
Two LVM VolGroup’s, same name, one is system disk – what to do?
It’s a lot easier to rename the “old” volume group if the old drive is the only one connected to the system.
Using your first FC4 installation CD and with only the old drive installed, boot into rescue mode (boot: linux rescue), but don’t search for or mount the FC installation. At the command prompt, you will probably need to active the lvm like this:
lvm vgscan
lvm lvscan
lvm vgchange -a y
lvm pvscan
lvm lvscan
The last two commands should list your volume group(s) and logical volume(s). Now use vgrename to fix the problem:
lvm vgrename VolGroup00 whatever_you_want_to_call_it
Note that all lvm commands need to be preceded with “lvm” in rescue mode.
via Two LVM VolGroup’s, same name, one is system disk – what to do?.
(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
lsof -i -n|grep http
via (98)Address already in use: make_sock: could not bind to address 0.0.0.0:80.
There was a cherokee server running that I didn’t know about that generated this error when trying to start httpd.
JBD: Barrier-based Sync Failed On md0-8 – Disabling Barriers Error and Solution
This is not a problem. This is just an informational log entry in /var/log/messages. Use the following commands to see the current status of your raid:
# cat /proc/mdstat
via JBD: Barrier-based Sync Failed On md0-8 – Disabling Barriers Error and Solution.
Vgdisplay, lvdisplay to display lvm components
vgdisplay
lvdisplay
Commands to list volume groups and logical volumes in a more civilized manner.
This link was posted in the past but not with regard to these commands which are very very useful when needed.
20 Linux System Monitoring Tools Every SysAdmin Should Know
Linux List The Open Ports And The Process That Owns Them
How do you list the network open ports on your server and the process that owns them? The answer is simple use the following command (must run as root):
sudo lsof -i
sudo netstat -lptu
via Linux List The Open Ports And The Process That Owns Them.
I don’t know why I keep forgetting this.
How to Bulk Rename Files in Linux (Terminal or GUI)
The syntax for the rename command is:
rename [ -v ] [ -n ] [ -f ] perlexpr [ files ]
-v means “verbose” and it will output the names of the files when it renames them. It is a good idea to use this feature so you can keep track of what is being renamed. It is also a good idea to do a test run with -n which will do a test run where it won’t rename any files, but will show you a list of files that would be renamed.
via How to Bulk Rename Files in Linux (Terminal or GUI) | Webmaster Tips.
scanning for new scsi devices
scanning for new scsi devices.
New devices can be added using echo “scsi add-single-device <h> <b> <t> <l>” > /proc/scsi/scsi where the variables are host, bus (channel), target (scsi id) and lun. The success (or otherwise) of this command can be determined by sending a subsequent cat /proc/scsi/scsi command.
..from the scsi-howto (proc interface) at www.tldp.org – see it for more info.
i have a script “rescan-scsi-bus.sh” here on debian which uses the above method to recheck devices.
HTH ritch.
This was written in 2005. I found the rescan-scsi-bus.sh script on medusa but have no idea which package it came from. It wasn’t on any other Fedora 14 install so it must have come from somewhere. It scans the SCSI bus and finds the drive perfectly well.
Re-scan the SCSI bus in Linux after hot-swapping a drive
A better way to find out the correct host controller:
# udevadm info -a -p /sys/class/scsi_generic/sg0
where sg0 is the device node of which you’d like to know the corresponding SCSI controller – down that tree you will find hostX mentioned as part of the device path.
And thanks for the rescanning tip, it saved my day.
via Re-scan the SCSI bus in Linux after hot-swapping a drive | Racker Hacker.