Zivo NiX BLog

Basically, tcptrack is a sniffer which will show the information about TCP connections on a specific interface. tcptrack will watch all the connections that occur and show the information in a nice interface. Although it’s on a text user interface but it’s simple and easy to understand. tcptrack has been packaged on several popular Linux distributions. The latest version of tcptrack is 1.2.0 released on December 20, 2006. You can download the source code from the tcptrack website.

tcptrack provides some useful information for administrators to track every single connection to their servers. I use tcptrack to watch my proxy to make sure that every user gets an apropriate bandwidth, no one saturates the whole bandiwdth. It just gives me a way to watch the traffic. The information that tcptrack provides are:

• source address and port
• destination address and port
• connection state
• idle time
• bandwidth usage

tcptrack also has a filtering feature, it uses the pcap filtering standard (it’s identic with the one used in tcpdump).

Installation

tcptrack installation is fairly easy, on Debian GNU/Linux or ubuntu you can simply use

apt-get install tcptrack

Searching on rpmfind.net I found the one matching my needs, tcptrack for CentOS. I use rpm for RHEL 4. I took the rpm and installed it manually. If you want to use yum, you have to enable the DAG repository. If you want to build it from source, you can read the INSTALL file in the package or read it online.

Using tcptrack

You have to be a superuser to run tcptrack, the basic usage of tcptrack is using such a command:

# tcptrack -i <networkInterface>

For example:

# tcptrack -i eth1

After invoking such a command tcptrack will run, capturing all TCP connections, and show it to you with an easy-to-understand interface. Another option that might be useful is -r and port. -r will make tcptrack wait for a given time (in seconds) before it deletes the closed connection from the screen. For example:

# tcptrack -i eth0 -r 10

port will do a filtering for you based on port number. For example:

# tcptrack -i eth1 port 22

You can read the manual for the complete options of tcptrack or read it online.

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http://wikis.sun.com/display/xvmOC1dot1/Managing+Solaris+Containers+With+Sun+xVM+Ops+Center

sweeet

ESXi 3.5 does ship with the ability to run SSH, but this is disabled by default (and is not supported).

1) At the console of the ESXi host, press ALT-F1 to access the console window.
2) Enter unsupported in the console and then press Enter. You will not see the text you type in.
3) If you typed in unsupported correctly, you will see the Tech Support Mode warning and a password prompt. Enter the password for the root login.
4) You should then see the prompt of ~ #. Edit the file inetd.conf (enter the command *vi /etc/inetd.conf*).
5) Find the line that begins with #ssh and remove the #. Then save the file. If you’re new to using vi, then move the cursor down to #ssh line and then press the Insert key. Move the cursor over one space and then hit backspace to delete the #. Then press ESC and type in :wq to save the file and exit vi. If you make a mistake, you can press the ESC key and then type it :q! to quit vi without saving the file.
6) Restart host or try kill -HUP `ps | grep inetd`

VMWare configured for Bridged, VMWare Tools installed. Mistake I made was booting the first time without checking that VMWare was set to Bridged and not NAT.

ifconfig -a plumb

found a pcn0 device and then

ifconfig pcn0 up
ifconfig pcn0 dhcp

Disks consist of the following:

1. Tracks - concentric rings on each platter
2. Cylinders - groups of tracks
3. Sectors/Blocks - 512 byte blocks

### Disk Partitions ###

Note: Partitions within Solaris are AKA slices
x86 PCs are limited to 4 FDISK primary partitions
Note: Solaris requieres 1 FDISK partition for its use

DISK - 72 GB

On x86 systems:
DISK Physical
FDISK Logical
Slices Logical

- 1 FDISK partition for Solaris use
- Slices are created within the single FDISK partition

Note: Solaris uses a VTOC - Volume Table of Contents to represent various slices within the lone FDISK partition on the disk.

Note: On Sparc, Solaris use VTOC to represent ALL slices on disk not withing lone FDISK

FDISK is not required in sparc

Slices rules within x86 using VTOC:
10 Slices ( 0 - 9 ) MAX maybe created using VTOC on x86
Slices 2, 8 , 9 are reserved
Slice 2 = VTOC

Note: VTOC represents the disk’s label and occupies Slice 2

0,1,3,4,5,6,7 - 7 Slices are available for use

Default Slice Allocation:

S0 - / (root) mount point
S3 - /var
S7 - /export/home

SPARC Disk Layout

Max of 8 slices 0 - 7
DISK0 - 72 GB

On Sparc:
DISK is physical
Slices are Logical

S0 - /
S3 - /var
S7 /export/home

Note: DIsk with ‘/ (root ) & /usr’ mount points is known as the system disk ‘ This disk is used to boot Solaris

All other disks attached to the system are known as secondary disks

### Print VTOC / Disk Label - using prtvtoc ###



# prtvtoc /dev/dsk/c0t0d0s0

* /dev/dsk/c0t0d0s0 partition map
*
* Dimensions:
* 512 bytes/sector
* 136 sectors/track
* 16 tracks/cylinder
* 2176 sectors/cylinder
* 65535 cylinders
* 65533 accessible cylinders
*
* Flags:
* 1: unmountable
* 10: read-only
*
* First Sector Last
* Partition Tag Flags Sector Count Sector Mount Directory
0 2 00 16779136 33556096 50335231 /
1 3 01 0 16779136 16779135
2 5 00 0 142599808 142599807
7 8 00 50335232 92264576 142599807 /export/home


/dev/dsk/c0t0d0s0 - Nomenclature

c0 - Controller #
t0 - is an identifier for bus - oriented controlled - first targed or id on the bus - first hard disk
d0 - represents disk number # first 0
S0 - represents the slice/partition