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Having to move large sums of data between boxes is part of an admins life… and sometimes those machines are across the country, and your moving a bunch of sensitive data, and the bosses want to make sure no one can sniff at it… ok, whatever boss

So here’s what I do, use friendly unix tar, and ssh pipe it to another machine.

Lemme show you some examples:
This shows you how to send files FROM the local machine TO a remote machine.

$ cd directory-with-files
$ tar cf - . | ssh username@remoteserver.com “cd /directory-to-put-files; tar xf -” [ENTER]

Ok, you may be asking me to explain this madness:
Change to a directory with files you want to transfer

tar cf - . - create a tar file, with the name “-”, which means output to screen, in the directory “.” (currently in, or right here)

| ssh username@remoteserver - setup an ssh connection to the remote server
“cd /directory-to-put-files; tar xf -” [ENTER] - once connected, change directorys on the local machine, and then EXTRACT that tar file named “-” or output to the screen.

In this case, the output to the screen will be piped thru ssh to the other computer and boom your set.

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Now, in order to reverse the logic and transfer FROM a server TO the local machine:

$ cd directory-to-put-files
$ ssh username@remoteserver.com “cd /directory-to-get-files; tar cf - .” | tar xf - [ENTER]

Try it out

Ok, this might sound insane, but this is the type of question you get asked sometimes, or the situation where you need to know comes up.

I was once asked what the current working directory was of a process on the server… often times I don’t even think about it, however the script was writing files, and we had no idea where

I tracked it down to a pretty simple method

> ps -awux | grep [process]

root 90 0.0 0.0 1016 228 ?? Is 27Apr05 1:01.81 /usr/sbin/cron

> ls -l /proc/[pid from above, which is 90]/cwd

lrwxrwxrwx 1 root root 0 Nov 4 12:56 /proc/90/cwd -> /var/spool

And it’s current working directory is /var/spool

Neat

Ok, I feel stupid, however I never realized that I could search man pages!

For those that don’t know, unix offers a built in “manual” command called “man”… sometimes it’s helpful, sometimes it’s there just for reference. It’s easy

$ man command

in this case man ls

LS(1) FreeBSD General Commands Manual LS(1)

NAME
ls - list directory contents

SYNOPSIS
ls [-ABCFGHLPRTWabcdfghiklmnopqrstuwx1] [file …]

DESCRIPTION
For each operand that names a file of a type other than directory, ls
displays its name as well as any requested, associated information. For
each operand that names a file of type directory, ls displays the names
of files contained within that directory, as well as any requested, asso-
ciated information.[and on and on]

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man is a great thing, however sometimes you end up forgetting the command your using, and thats when my new little friend helps out…

$ man -k search-scring[ENTER]

This is awsome, now I can find all the insane instances of locate man -k locate

cfree(3) - free up allocated memory
index(3) - locate character in string
locate(1) - find filenames quickly
locate.updatedb(8) - update locate database
memchr(3) - locate byte in byte string
mmap(2) - allocate memory, or map files or devices into memory
pthread_mutex_destroy(3) - free resources allocated for a mutex
rindex(3) - locate character in string
strchr(3) - locate character in string
strpbrk(3) - locate multiple characters in string
strrchr(3) - locate character in string
strstr(3), strcasestr(3), strnstr(3) - locate a substring in a string
usbhid(3), hid_get_report_desc(3), hid_use_report_desc(3), hid_dispose_report_desc(3), hid_start_par
se(3), hid_end_parse(3), hid_get_item(3), hid_report_size(3), hid_locate(3), hid_usage_page(3), hid_
usage_in_page(3), hid_init(3), hid_get_data(3), hid_set_data(3) - USB HID access routines
whereis(1) - locate programs
which(1) - locate a program file in the user’s path

Give it a whirl!

Knoppix is a great bootable live operating system for x86 machines (ya know, intel boxes, windows boxes) that gives you a full XWindows implementation with utiltiies, network connectivity, and more..

I’ve used this to save my butt so many times when an OS won’t boot and I need to get to the data on the drives, or edit a config file, or even just to troubleshoot a friends PC.. I suggest getting it up on your USB keychain device and BURNING A FEW SPARE CD’S WITH IT.

I keep one in the car, in a ziplock bag just in case

Go Grab Knoppix now.