tcpdump command and options

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tcpdump - dump traffic on a network. Tcpdump prints out a description of the contents of packets on a network interface that match the boolean expression.

Type the following command:

$tcpdump

You need to interrupt the command else it would keep scrolling

http://unix.stackexchange.com/questions/82919/what-does-the-eth0-interface-name-mean-in-linux

OPTIONS

-i interface

--interface=interface Listen on interface. If unspecified, tcpdump searches the system interface list for the lowest numbered, configured up interface (excluding loopback), which may turn out to be, for example, ``eth0''.

$tcpdump -i eth0

-c count

Exit after receiving count packets.

$tcpdump -c 30 -i eth0

-D

--list-interfaces, prints the list of the network interfaces available on the system and on which tcpdump can capture packets. For each network interface, a number and an interface name, possibly followed by a text description of the interface, is printed. The interface name or the number can be supplied to the -i flag to specify an interface on which to capture.

$tcpdump -D

-w file

Write the raw packets to file rather than parsing and printing them out. They can later be printed with the -r option.

$tcpdump -w dump01.pcap -c 10 -i eth0

and now read the dumped file -

$tcpdump -r dump01.pcap

-n Don't convert addresses (i.e., host addresses, port numbers, etc.) to names.

$tcpdump -n

To capture packets from specific port, specify port number -

$tcpdump -i eth0 port 22

To capture packets from specific source -

$tcpdump -i eth0 src 192.168.1.1

How can you save resources when instantiaing driver?

I asked on my previous post about what was wrong in instantiating driver on set up method? And here is the solution video on my YouTube channel (After 5 years of gap I finally added new video tutorial :)) The solution described on video tutorial uses following set up - public class BaseClassOnDemandDriverSetup { private WebDriver driver ; @BeforeMethod public void setupTest () { // Any other set up goes here } @AfterMethod public void teardown () { if ( driver != null ) { driver .quit() ; } } public WebDriver getDriver () { if ( driver == null ) { WebDriverManager. chromedriver ().setup() ; driver = new ChromeDriver() ; } return driver ; } }

Using chrome console to test xPath and css selectors

Since the advent of selenium there have been many plugin to test xPath / css selectors but you don’t need any of them if you have chrome browser. Using Chrome console you can test both xPath and css selectors. Launch website to be tested in chrome browser and hit F-12 and you would see chrome console opened in lower pane of application - Hit escape key and console would open another pane to write element locators - And now you can start writing xPath or css selectors in chrome console and test them - The syntax for writing css id - $$(“ ”) And hit the enter key. If your expression is right then html snippet of the application element corresponding to the css selector would be displayed - If you mouse over the html snippet in chrome console then it would highlight the corresponding element in application - If you want to clean console of previously written element selectors then just hit ctrl+L keys and chrome console would be empty again. Pro

Using xPath to reach parent of an element

Well, I am big fan of css locator my self there are times when css locators don't fit requirement. One such requirement is when you want to navigate to parent element of an element and may be parent of parent and even more. Unfortunately css locators don't provide any mechanism to navigate to parent of an element. See this for more. Of late I came across a scenario when I wanted to click on a link depending upon the text in a text box. Herein parent of text box and parent of link were at the same location. More over there could have been many such combinations in application. Fortunately I just need to pick first such instance and Web Driver any way considers only first instance when multiple locators are found matching an element. Element in question is in following html - Here I need to click on highlighted anchor on the basis of input element (which is also highlighted in image) Herein first I need to reach div parent (class = 'left couponmainarea

No Automated Testing

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