I am seeing a lot of TCP failed connection attempts from "netstat -s" on one of our servers.
How can I pin point what connection failed and what are the ports involved?
Any tools/commands I can dig in deeper to diag. what went wrong on these "failed connection attempts"?
Thanks!
Last edited by Scott; 03-01-2010 at 08:04 PM..
Reason: Added code tags
Hi. I would like to be able to deny IP address for too many failed login attemps (either from ssh, sftp, ftp, etc). The system I wish this to work on is an AIX 5.1 system. I'm new to AIX but I'm a linux user. There is a program for linux called fail2ban which reads from the log files and see if... (1 Reply)
Hi,
I have created the below ftp script to put files over to our capacity server, the check at the end works if ftp fails to run however if the script cannot login or the transfer itself failed there is no warnings.
Does anyone know the syntax to trap the erorr codes or to put a check within... (3 Replies)
Hi Experts,
need help about release or refresh TCP Connection:
i have the sample like below :
application log connection:
0500 ( 192.168.0.1:36053) 00919 2007/05/10 23:30:25 112 13 2007/05/10 23:30:25 1969/12/31 17:00:00
0500 ( 192.168.0.1:36054) 00920 2007/05/10 23:30:26 000 00... (3 Replies)
I wrote a very simple script to calculate the DB connection from an appserver and check the total netstat connection to a particular DB exceed 25 then it will send mail
netstat -a 2> /dev/null | awk '/.*ESTAB/{print $5}' | cut -d. -f1 | uniq -c | awk '{if ($1 > 25)print $2," exceed ",$1;}'
... (1 Reply)
Hello,
Actually there are some bugs in application which does not close the TCP connection to other server though CORBA.
We need to kill that ESTABLISHED connections as new connection are not happeneing as the allocated ports were used and showing as ESTABLISHED
Is there any... (4 Replies)
Hey all I'm having a big problem here. Someone is attempting an SSH to a destination host on which an account resides and locking the account. I'm trying to determine who is performing the SSH attempts from my host. For instance they're logged in as their standard account but then (I'm assuming)... (13 Replies)
Hello
netstat -p give below 6634176 connections as closed.How do we trace that which all connections are being closed on the server?
1366888371 data packet headers correctly predicted
1195906 connection requests
5227320 connection accepts
5992919... (6 Replies)
The purpose of this thread is for everyone to follow the same methodology so we can create a future table, for the benefit of all, that shows how many failed login attempts (hacking) per day per server (and per minute) are happening.
This is not a thread on writing scripts or creating... (10 Replies)
Discussion started by: Neo
10 Replies
LEARN ABOUT ULTRIX
rexecd
rexecd(8c)rexecd(8c)Name
rexecd - remote execution server
Syntax
/etc/rexecd
Description
The command is the server for the routine. The server provides remote execution facilities with authentication based on usernames and
encrypted passwords.
The command is invoked by when it receives a connection on the port indicated in the ``exec'' service specification. For further informa-
tion, see When a service request is received the following protocol is initiated:
1) The server reads characters from the socket up to a null (` ') byte. The resultant string is interpreted as an ASCII number, base 10.
2) If the number received in step 1 is non-zero, it is interpreted as the port number of a secondary stream to be used for the stderr. A
second connection is then created to the specified port on the client's machine.
3) A null terminated username of at most 16 characters is retrieved on the initial socket.
4) A null terminated password of at most 16 characters is retrieved on the initial socket.
5) A null terminated command to be passed to a shell is retrieved on the initial socket. The length of the command is limited by the upper
bound on the size of the system's argument list.
6) The command then validates the user as is done at login time and, if the authentication was successful, changes to the user's home
directory, and establishes the user and group protections of the user. If any of these steps fail the connection is aborted with a
diagnostic message returned.
7) A null byte is returned on the connection associated with the stderr and the command line is passed to the normal login shell of the
user. The shell inherits the network connections established by
Diagnostics
All diagnostic messages are returned on the connection associated with the stderr, after which any network connections are closed. An
error is indicated by a leading byte with a value of 1 (0 is returned in step 7 above upon successful completion of all the steps prior to
the command execution).
username too long
The name is longer than 16 characters.
password too long
The password is longer than 16 characters.
command too long
The command line passed exceeds the size of the argument list (as configured into the system).
Login incorrect
No password file entry for the username existed.
Password incorrect
The wrong was password supplied.
No remote directory
The command to the home directory failed.
Try again
A fork by the server failed.
/bin/sh: ...
The user's login shell could not be started.
Restrictions
Indicating ``Login incorrect'' as opposed to ``Password incorrect'' is a security breach which allows people to probe a system for users
with null passwords.
See Alsoinetd(8c)rexecd(8c)