Quick and Dirty Port Check (ch.pl v 0.1)
The core of the following script is based off work first started by my coworker Trent. The gist of the little script is to perform a quick scan of a hostname or IP by simply attempting to open a socket. I use this when I want to run a quick “is it online” scan of a server and determine if ports of interest are available to me. I added the bit that would let me open them directly from the script without having to type in an alternate command.
This is very much a poorly written hack-job script, and I very much expect that some of you will be able to identify some serious n00b mistakes (probably in that I still haven’t figured out how to properly localize variables), but hey, I don’t think this is half bad for my first PERL script. Yes, PERL. I’ve already been lectured about learning Python instead, but while that’s definitely on the to-do list, this script needed finishing, and I was already halfway through. It’s a tool that’s customized for me, so please hack away, and let me know what you do, as I may like it too!
So, I present, for your consideration and for your critique (please do), ‘ch.pl’ v 0.1.
I generally alias ch=/usr/local/bin/ch.pl for this script in Linux and MacOS, as this lets me leave the file extension the same for when I use it in Windows. To use this in Windows, you’ll need to install PERL first. I use ActivePerl. However please note, I’m still working on making this script Windows friendly.
To install in Linux/MacOS:
- download ch.pl using FTP or wget to /usr/local/bin/
- chmod +x /usr/local/bin/ch.pl
- modify your ~/.bash_aliases file (ubuntu), or your ~/.bashrc (RedHat) to include the following:
- ‘alias ch=/usr/local/bin/ch.pl’
Usage: ch [hostname or IP] [optional: port(s) to check, separated by commas]
Preview: Handy Sysinternals Utilities
This article was first published as “Locked Files in Windows” on 22 Jul 2009.
Note to self: Sysinternals is Microsoft’s saving grace:
Process Explorer: A more advanced taskmgr, if you will. It’s most awesome feature is it’s ability to search for processes holding a certain handle, allowing you to resolve locked file issues:
Home page: http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx
Or just run it from http://live.sysinternals.com/procexp.exe
Process Monitor: Basically, Regmon + Filemon:
Home page: http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx
Or just run it from http://live.sysinternals.com/Procmon.exe
Check Your OS’s Installation Date
Linux:
ls -alh /boot/grub #the majority of files in this folder don’t change from the time of install except for menu.lst
ls -alh /restore #BSD
Windows:
Systeminfo #from the command line
- or –
CMD /K WMIC OS GET InstallDate
You’ll see the Operating System installation date (in WMI format). The first eight characters in that output gives you the installation date.
*Windows bit stolen from http://windowsxp.mvps.org/getosdate.htm
Make a Fat32 Partition in Linux
This is handy for transferring files between Windows and Linux, as many distro’s don’t have NTFS RW support built in. This is, of course if you do not have access to the NTFS-3G driver, which does allow for RW mounts.
Overview: fdisk w/ a W95 partition table
mkdosfs
If you need the step by step, it’s below:
fdisk /dev/sd(whatever drive you want to reparition, ‘b’ in this case), then follow along:
The number of cylinders for this disk is set to 20023.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)
Command (m for help): m
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition’s system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality (experts only)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-20023, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-20023, default 20023):
Using default value 20023
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): c
Changed system type of partition 1 to c (W95 FAT32 (LBA))
Command (m for help): p
Disk /dev/sdb: 164.6 GB, 164696555520 bytes
255 heads, 63 sectors/track, 20023 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x000f0136
Device Boot Start End Blocks Id System
/dev/sdb1 1 20023 160834716 c W95 FAT32 (LBA)
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: If you have created or modified any DOS 6.x
partitions, please see the fdisk manual page for additional
information.
Syncing disks.
root@sbrescue:/# mkdosfs /dev/sdb1
mkdosfs 3.0.1 (23 Nov 2008)
root@sbrescue:/# mount /dev/sdb1 /mnt
root@sbrescue:/# cd /mnt
root@sbrescue:/mnt# touch asdf
root@sbrescue:/mnt# ls
asdf
root@sbrescue:/mnt#
All done! =D
Hostnames Greater than 15 Characters Effectively Disables MSFTPSvc.
Wait, what?! Oh yeah. It just grinds to a halt, without any helpful error messages. This is just another thing that I want to jot down so I know to check for it the next time I run across a server with FTP issues.
AFAIK, it has to do with a NETBIOS limitation.
