Question-DOS commands

[Ghostgirl705]

I was wondering if any of you could tell me about DOS commands. This is for a homework assignment. I normally wouldn't post this but I don't know where else to go or look. And mods if this is not right for the CL please move it...I couldn't find any other appropriate forums

tracert-- the IP addresses it spits out, how can I follow the path the packet took?

ping-- the TTL, what does it start at? At 1 going up or some number going down?

arp--I know that -a will tell me my MAC but what does this and ping and tracert tell me about my IP configuration?

My book has nothing about DOS commands and all the internet sites are such geek speak that I don't understand them.



EDIT: Thank you!!!

[gerbick]

where you been!?

tracert will list out the "hops" between you and the destination via the cmd prompt. it'll be a list... 'tis easy to understand.

arp is for address resolution protocol... it'll display the current arp entries of your target... but it's something that's rarely used.

ping? you send a packet out to a server, it responds... think sonar. ping... ping.

[Ghostgirl705]

so for tracert, my question is to "describe the path my packet took" All the hops are the IPs the the packet stops over at? How would I describe this? Like a truck stop on the way from California to New York?

And what do all three of these commands tell me about my IP address?

[hanratty21]

tracert will tell you each hop as such:
Client Machine (some IP addr) - 0 ms (time it took)
Your router (another IP) - 2 ms
your ISP (IP again) - 10 ms (or some other #)
your ISP's ISP (IP#) - 8 ms....

etc....
until...
www.flashkit.com (some IP) - 11 ms.

Truck stop is an ok analogy. Keep in mind though, that the hops may or may not always be the same. I'd equate it more to a pinball bouncing around a machine...it'll end up in the hole eventually, (no jokes gerbick) but may make a few bounces along the way.

RH

[gerbick]

tracert is short for trace route. it's like... "how I got from my computer, through my ISP, through the woods, over the river, and to my target"... in a logical network manner from your IP address... it's all relative to your IP address being the beginning start point.

ping... it's a ping from your IP address to the desired target... just to see if it's responding.

for your local IP address... at the C:\ prompt, hit up ipconfig /all for all of your local IP address stuff(s)...

[gerbick]

curse you and your "no jokes" rule!

[hanratty21]

for your local IP address... at the C:\ prompt, hit up ipconfig /all for all of your local IP address stuff(s)...

unless you want your public facing IP address. The above will give you your local one - not the one that the internet "sees" you as.

For the public one, www.ipchicken.com always works for me.

[hanratty21]

curse you and your "no jokes" rule!

it was going to be too easy. I'd rather you wait until there's a REAL opportunity!
ball in the hole? come on -- too easy!

[gerbick]

bah! I just view my router for that

c'mon... lift the "no joke" ban already!

damn. I missed something... thanks Jeff2A. You da' man.

[Jeff2A]

ping-- the TTL, what does it start at? At 1 going up or some number going down?

Nobody actually answered the question about the TTL, so I will ...

TTL is short for 'time to live' - how many hops that packet is allowed to take before it's dropped by routers on the internet.

The default is 64 - your ping packet (technically an IP packet called ICMP, with a special code set to indicate that it's an 'echo request') will go 64 hops before it's dropped. When it reaches its destination, the receiving computer (usually) will send back an ICMP packet with type set to 'echo response' indicating that it is alive and responding.

At each router/computer, it will decrement (64, 63, 62, ...), and when it hits 0, it will fail - the router at that point SHOULD send back an ICMP packet with TTL-exceeded. Generally, more than 32 hops indicates a routing loop OR (occasionally) a very complex, international network.

If you want to make sure that the packet only goes to 'local' machines, you can set TTL=1 (ping -i 1 ) so that the packet will not cross any routers.

[Ghostgirl705]

So now tell me how you guys just made everything so clear in 15 mins. I have been on the net for 2 days trying to figure this out. Grrrr

pinball analogy is perfect! You should have seen the freaking light blub go off over my head