Re: Telnet list of IP and get information stored to a file

Some problems I see without running the code:

You read from the IPS handle, but don't remove the line endings. Add a chomp as first command of the while loop.
3.3.3.* is neither a valid IPv4 address nor a valid host name, thus Net::Telnet will never be able to connect. You need to expand * in your code.
The same applies to 3.3.9.*.
I don't see any method calls for the $telnet object (open, getline, close).
Confusing indent.
Missing error checks at least for open OUT
You are opening OUT more than once.
From the error messages, there seems to be a problem with your input file, but the error messages should not happen with the code you posted. Did you post the code that actually generated the error messages?

Apart from that, I think that a simple nmap port scan should do the job, you don't need Perl for that.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

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Re^2: Telnet list of IP and get information stored to a file by sanju7 (Acolyte) on Jul 26, 2010 at 15:04 UTC
The list has some 300 IP address or network. It means so many thousands of IP address, I don't know how nmap would be useful here. The best logis i figured, (a) read the list (b) pick the ip address and process it (c) if ip address has asterisk(x.x.x.) expand it to its all possible ip addresses (x.x.x.1/2/3..254) . (d) process it by script. (e) if telnet successful the app would throw its name etc .. record it on a file. (f) if fails go to next ip address. So the expansion is still a big deal here because 85% of the list is ip addresses like 3.3.3. (yy.xxx.zz.*) format. I am thinking of Regex here. About error: Since my code woould fail to expand ip addresses which has last quadrant I tested the it with a IP list consisting of localhosts like below, `127.0.0.1 127.0.0.1` [download] If you know any easier way to expand the list of IP which has asterisk at last quadrant to the whole network i can test that portion. And yes this code is the one that has generated the error, i haven't altered things except IP list etc.	[reply] [d/l]
Re^3: Telnet list of IP and get information stored to a file by afoken (Chancellor) on Jul 26, 2010 at 19:39 UTC
The list has some 300 IP address or network. It means so many thousands of IP address I wonder what reason one could have to try a port scan against such a large list. If you legally own (or use) that many systems, you should have a network management system making such strange scans unnecessary. I also wonder why you want to access machines owned by General Electrics (3.0.0.0/8) and the United States Department of Defense (22.0.0.0/8). I don't know how nmap would be useful here. Well, perhaps you should start reading the nmap documentation. nmap can be configured to scan entire net blocks. It can be configured to scan only one or a few selected ports. It can read a list of scan targets from a file. It can be configured to scan by establishing a TCP connection. It can scan in parallel. And it can be configured to do all this at once. And of course, nmap can write a report in various formats, like XML, HTML and plain text. nmap is the wheel you want to reinvent (and much more). Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply]
Re^4: Telnet list of IP and get information stored to a file by sanju7 (Acolyte) on Jul 26, 2010 at 22:03 UTC
I must clarify here IP addresses are fictitious, my bad i should have symbolized it properly. I just choose the digits came to my mind by repeating them in each block. The reason for doing telnet it to count the presence of valid application which listens to a certain port. Thats generally easy when doing only few ip addresses. The reason to scan blocks of IP is because its not clear which ip in network is available(up and on) i.e basically simplify the search. (a)If its valid system then would respond to telnet / port (b) if not then it would quit In general its a reporting work should have been reported by some other way (but as circumstance required information which i was trying to get), as in a application which is present in many places largely separate remote networks it seems easy to telnet a certain port of a server staying within org network rather than connecting each GUI of the each app remotely etc and check manually	[reply]
Re^5: Telnet list of IP and get information stored to a file by afoken (Chancellor) on Jul 27, 2010 at 11:47 UTC