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1. AIX
Hi,
I understand that, we can use SSH/SSL for encrypted/secure sessions. my question is " can we secure telnet on AIX " ?
usually, we disable network services like ftp, telnet etc.
and replace it with SFTP, SSH.
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2. AIX
I work for a health care company part of my job is to run checks we use a telnet session that we use AIX 6 commands. I have almost no programming experience but i want to learn it, we have a programmer here but he has no time my question is,, Is there anything that allows you to program a GUI... (7 Replies)
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3. AIX
hello,
i am trying to test connection to a 5.3 box. from an xp machine, telnet connects but shows only a blank screen. cursor moves as i type, but no response back.
have used telnet, putty and accuterm - all same result
verified that telnet services are active in xp
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4. AIX
Hi all,
I have 2 servers (Oracle & Weblogic) in 1 AIX box (Different partition). I recently had done a security hardening to this AIX box. And it disable the FTP and TELNET functions of both servers. I manage to recover the settings for the Oracle server but i have totally no access to the... (2 Replies)
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5. AIX
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6. AIX
I have intermec handheld device which is connecting to AIX Server on port 12431 or whatever. ( oracle application )
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7. UNIX for Dummies Questions & Answers
Hello,
I have AIX 5.3 at home connected to netgear router. Port Forwarding has been enabled on the router. Problem is that if I want to telnet, I have to try 2 or 3 times before I can get a logon prompt. It times out for first or second time (Connection to session <IP_Address> failed: Connection... (1 Reply)
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8. AIX
Greetings. . .Can anyone out there explain how I would turn off the telnet service and close the telnet port on a AIX system?
Thank you,
outta. (2 Replies)
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9. AIX
We're having problems getting disconnected from AIX with our telnet sessions.
I can't ping the server when this happens, either. Other serves can be pinged at the same time.
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Discussion started by: e1lyons
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10. AIX
Can somebody help me. Whenever I telnet to my server i received a message
/dev/pts/0: 3004-004 You must "exec" login from the lowest login shell.
Connection closed.
pls help me (2 Replies)
Discussion started by: vjm
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NC(1) BSD General Commands Manual NC(1)
NAME
nc -- arbitrary TCP and UDP connections and listens
SYNOPSIS
nc [-e command] [-g intermediates] [-G hopcount] [-i interval] [-lnrtuvz] [-o filename] [-p source port] [-s ip address] [-w timeout]
[hostname] [port[s...]]
DESCRIPTION
The nc (or netcat) utility is used for just about anything under the sun involving TCP or UDP. It can open TCP connections, send UDP pack-
ets, listen on arbitrary TCP and UDP ports, do port scanning, and source routing. Unlike telnet(1), nc scripts nicely, and separates error
messages onto standard error instead of sending them to standard output, as telnet(1) does with some.
Destination ports can be single integers, names as listed in services(5), or ranges. Ranges are in the form nn-mm, and several separate
ports and/or ranges may be specified on the command line.
Common uses include:
o simple TCP proxies
o shell-script based HTTP clients and servers
o network daemon testing
o source routing based connectivity testing
o and much, much more
The options are as follows:
-e command
Execute the specified command, using data from the network for stdin, and sending stdout and stderr to the network. This option is
only present if nc was compiled with the GAPING_SECURITY_HOLE compile time option, since it allows users to make arbitrary programs
available to anyone on the network.
-g intermediate-host
Specifies a hop along a loose source routed path. Can be used more than once to build a chain of hop points.
-G pointer
Positions the "hop counter" within the list of machines in the path of a source routed packet. Must be a multiple of 4.
-i seconds
Specifies a delay time interval between lines of text sent and received. Also causes a delay time between connections to multiple
ports.
-l Is used to specify that nc should listen for an incoming connection, rather than initiate a connection to a remote host. Any host-
name/IP address and port arguments restrict the source of inbound connections to only that address and source port.
-n Do not do DNS lookups on any of the specified addresses or hostnames, or names of port numbers from /etc/services.
-o filename
Create a hexadecimal log of data transferred in the specified file. Each line begins with ``<'' or ``>''. ``<'' means "from the
net" and ``>'' means "to the net".
-p port
Specifies the source port nc should use, subject to privilege restrictions and availability.
-r Specifies that source and/or destination ports should be chosen semi-randomly instead of sequentially within a range or in the order
that the system assigns.
-s hostname/ip-address
Specifies the IP of the interface which is used to send the packets. On some platforms, this can be used for UDP spoofing by using
ifconfig(8) to bring up a dummy interface with the desired source IP address.
-t Causes nc to send RFC854 DON'T and WON'T responses to RFC854 DO and WILL requests. This makes it possible to use nc to script telnet
sessions. The presence of this option can be enabled or disabled as a compile-time option.
-u Use UDP instead of TCP. On most platforms, nc will behave as if a connection is established until it receives an ICMP packet indi-
cating that there is no program listening to what it sends.
-v Verbose. Cause nc to display connection information. Using -v more than once will cause nc to become even more verbose.
-w timeout
Specifies the number of seconds nc should wait before deciding that an attempt to establish a connection is hopeless. Also used to
specify how long to wait for more network data after standard input closes.
-z Specifies that nc should just scan for listening daemons, without sending any data to them. Diagnostic messages about refused con-
nections will not be displayed unless -v is specified twice.
EXAMPLES
nc
Wait for the user to type what would normally be command-line arguments in at stdin.
nc example.host 42
Open a TCP connection to port 42 of example.host. If the connection fails, do not display any error messages, but simply exit.
nc -p 31337 example.host 42
Open a TCP connection to port 42 of example.host, and use port 31337 as the source port.
nc -w 5 example.host 42
Open a TCP connection to port 42 of example.host, and time out after five seconds while attempting to connect.
nc -u example.host 53
Send any data from stdin to UDP port 53 of example.host, and display any data returned.
nc -s 10.1.2.3 example.host 42
Open a TCP connection to port 42 of example.host using 10.1.2.3 as the IP for the local end of the connection.
nc -v example.host 42
Open a TCP connection to port 42 of example.host, displaying some diagnostic messages on stderr.
nc -v -v example.host 42
Open a TCP connection to port 42 of example.host, displaying all diagnostic messages on stderr.
nc -v -z example.host 20-30
Attempt to open TCP connections to ports 20 through 30 of example.host, and report which ones nc was able to connect to.
nc -v -u -z -w 3 example.host 20-30
Send UDP packets to ports 20-30 of example.host, and report which ones did not respond with an ICMP packet after three seconds.
nc -l -p 3000
Listen on TCP port 3000, and once there is a connection, send stdin to the remote host, and send data from the remote host to stdout.
echo foobar | nc example.host 1000
Connect to port 1000 of example.host, send the string "foobar" followed by a newline, and move data from port 1000 of example.host to std-
out until example.host closes the connection.
SEE ALSO
cat(1), telnet(1)
The netcat README.
AUTHOR
*Hobbit* [hobbit@avian.org]
BSD
August 1, 1996 BSD