Is it possible to restrict telnet connection from remote to my server(linux -centos5)?
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Ex : [root@localhost]# telnet 10.0.0.33 80
Trying 10.0.0.33...
[code]...
I am able to telnet to the server via a remote connection, but for some reason, it will not accept mail. ere is the bounce back email I am getting.Quote:This is the mail system at host smtp.mydomain.net.I'm sorry to have to inform you that your message could notbe delivered to one or more recipients. It's attached below.For further assistance, please send mail to postmaster.If you do so, please include this problem report. You candelete your own text from the attached returned message.The mail system
<root@mydomain.net>: temporary failure. Command output: pipe: fatal: pipe_command:
execvp /usr/bin/perlbin/vendor/spamc: No such file or directory
Reporting-MTA: dns; smtp.mydomain.net
[code]....
I can telnet (while on the actual machine) using
Quote:
telnet localhost 25
When I try and use the local machine's ip
Quote:
telnet 192.168.100.9 25
I get
Quote:
Trying 192.168.100.9...
telnet: Unable to connect to remote host: Connection refused
[Code].....
This last one is strange as I the IP looks odd.
What I am doing wrong, and how do I fix it. After much surfing many mosts say that telnet is not used anymore but I want to use it to test my smtp server.
My system is Ubuntu 11Before I typed "telnet localhost" or "telnet localhost 23". I have make this work below:$sudo apt-get install xinetd$vim /etc/xinetd.conf
defaults{
instances=60
log_type=SYSLOGauthpriv
[code]....
when i try a telnet to a host like that: telnet 10.10.10.10 1234 i got this: telnet: Unable to connect to remote host: Connection refused.
1/ does this mean that the problem is not due to a firewall, but that the host 10.10.10.10 doesn't listen on the port 1234? other way does this mean that my firewall is authorizing traffic on the port 1234?
and when i try a telnet on another port like that: telnet 10.10.10.10 1235 i get: Trying 10.10.10.10 ...
in this case this
2/ does this mean that the firewall is blocking the traffic between my host and the 10.10.10.10 on the port 1235?
I am running CentOS 5.1 on VMware on Win 7 On CentOS I added Bridged network adapter and the server is connected to internet without any problems, but when I telnet any server on port 25 I get connection timeout.
Code:
telnet f.mx.mail.yahoo.com 25
Trying 98.137.54.237...
telnet: connect to address 98.137.54.237: Connection timed out
telnet: Unable to connect to remote host: Connection timed out
I stopped all servers, iptables and sendmail on the linux server and the firewalls on the win 7 but still getting the same error! I added new network adapter ( host-only ) and tried to telnet the win machine from vmware Linux but I got connection refused
Code:
telnet 192.168.71.1 25
Trying 192.168.71.1...
telnet: connect to address 192.168.71.1: Connection refused
telnet: Unable to connect to remote host: Connection refused
[code]....
When i am trying to telnet to a machine connected in our LAN ..
telnet: Unable to connect to remote host: Connection refused
What's the reason for this? how do i establish a connection? I am using ubuntu 10.04.
I did followings:
Code:
But got:
Code:
But as I tried:
Code:
It's OK.
I am doing some R&D on 11g RMAN in oracle at home. i have installed oracle enterprise linux and i have installed oracle software. when i am trying to configure listener, it is error-ed out. i have verified that telnet with the port is not working and i am seeing connection refused error.
View 3 Replies View RelatedI'm trying to test smtp connectivity to my postfix configuration and I can telnet to port 25 from the computer itself but cannot from the outside. I get a connection refused error message. What am I doing wrong? I believe my dns is setup correctly as it seems the telnet can hit the box so I'm fairly sure its not that.
View 14 Replies View RelatedOk, a bit of a backround. I am a recent Ubuntu user and made the switch to Fedora being utilized as a server. I am trying to move to a new MUD(text based D&D type game) codebaseI have gotten my code compiled and executed the startup script. The process shows in the ps ux list. As the game it set up it uses port 7500. As the script running I get a "Connection Refused" error when trying to telnet to port 7500. Upon using nmap, I show only my SSH port open (the only daemon I have installed currently) yet no port 7500 open.
I believe this to be an issue somewhere in Fedora as I've had no issue on Ubuntu with past MUD codebases.I have disabled the firewall within Fedora and still no luck. Please bare with me as I'm new to fedora's intricacies.Short Story for those that hate reading long winded posts: A port that should be open by acript known to work on other distro's doesn't seem to open the called port using Fedora
I want restrict telnet session to users.
That means the client login one user at a time. not multiple login.
For example:
I want restrict this. How to restrict one user to use multiple login.
I'm trying to make an SSH script for my place of employment. This script, I want to go out to the server hostnames we have specified (in another file) and change a users account password. We use Kerberized telnet, so if telnet root hostname fails, I want it to use ssh username hostname and use the old password (specified). If both fail, I want it to ask the user what the port should be and input the port in the ssh command.
But I'm having a issue having it try telnet root hostname and if it fails then, try to ssh in, I have no clue how to have it proceed. Is it an if statement? Here's the telnet failed message: telnet: Unable to connect to remote host: Connection refused
I have had a look at the the information on the ubuntu forum about this but am having trouble getting the server to do what i want it to do.
I have a VPS running ubuntu 9.10 and i am trying to set it up to redirect port 25 to a remote machine via a VPN connection (remote machine connected via VPN)
i have tried setting this up in the firewall using webmin but it is not working.
I'm trying to connect with my server via telnet, but when i sent the command (telnet xxx.xxx.xxx.xxx Port) doesn't works and shows then follow error: Unable to connect to remote host: Connection refused, It happens with any port. Is strange but my telnet services works (telnet xxx.xxx.xxx.xxx), In addition, i tried with firewall enabled and disabled and the problem still happens. My centOS run on virtualbox.
View 3 Replies View RelatedI have configured rssh 2.3 with openssh 5.8 on RHEL 5.6 64 bit to restrict the users to scp and sftp. When i try to sftp or scp it gives error connection closed. After long googling tried different solutions like add missing libraries, setuid to rssh_helper. I had full copy of /lib to /chroot/lib and /chroot/lib64 but no success. conf and log files are below for reference.
[Code]...
The issue is that my CentOS workstation is in a vlan from where the Intranet's DNS servers are unreachable. For browsing the web there is an ISA proxy server, which I presume resolves DNS for my firefox. However, wget, host, ping and aria2c fail to get any sort of DNS resolution since they're being run from command line.I have exported HTTP_PROXY value, which provides me internet access on console, but,only when I connect using IP address. It fails on name resolution.
My question is:May I redirect the DNS queries to my home PC which would be running a DNS server on a non standard port?I was thinking of putting nameserver 127.0.0.1 in /etc/resolv.conf and then put iptables rule to redirect 127.0.0.1:53 UDP to a.public.ip.address:3535 UDP..I don't know if I am shooting blanks or what, I am not very much aware of this kind of setup.My main need is to provide DNS resolution to console apps.I want to utilize my company's idle bandwidth for bulk downloads, so, using proxy, SSH tunneling through my Home PC is out of question.
Friday night I was working on some networking stuff between my two Fedora 14 boxes. I have my laptop and my desktop. on both machines I have "system-config-firewall 1.2.27" and "iptables" (i believe both come standard on F14?) I kept getting the same message as seen below before realizing perhaps I should check my firewall!
I added a rule for incoming and outgoing traffic on port 22 and was able to get in with no problems at all! however today I can't ssh into anything... I can't use "Remote Desktop Viewer 2.31.4" to vnc into the machine anymore. I can't remember the exact error message at this time, it's something close to "Connection was terminated" or "Unable to connect" I can update this message later.
last night I foolishly uninstalled the system-config-firewall and then uninstalled iptables to see if it was a simple firewall issue.... totally hosed my system <insert smiley!>
After reinstalling and realizing I didn't backup my documents <insert smiley!...again...> I started reinstalling all of my applications. I'm still unable to use ssh and I've tried to ssh my own computer.
Is this possible?
# ssh 127.0.0.1
ssh: connect to host 127.0.0.1 port 22: Connection refused
I've setup a FTP server in OpenSUSE 11.1 with KDE 3.5.x. (Pure-ftpd) But when I connect with an user to the FTP server I can browse to all folders on the OPENSUSE system, how can I setup one folder for all users and restrict the FTP connection to that folder only??
View 1 Replies View Relatedconfigure nagios to monitor custom port on a remote linux server..
View 5 Replies View RelatedI am merely trying to change the port for my ssh server.However it isn't changing.I edited my ssh_config file to:
Code:
# This is the ssh client system-wide configuration file. See
# ssh_config(5) for more information. This file provides defaults for[code]...
When i try to connect to my server via port 443 i get a connection refused error. However when i try to connect via port 22 it connects. Since that didn't work, i tried restarting the entire server.To restate, i changed the config file and restarted ssh then the computer, however the port didn't change.Ohh and yes my router is set to port forwarding on port 443, though it doesn't matter since I'm inside the network.
I am trying to open the telnet port on my system with port 4100 and for the same i have inserted the entries in iptables file using below command./sbin/iptables -A INPUT -s 132.186.208.83/24 -p tcp �-dport 4100 -j ACCEPT.
View 1 Replies View RelatedWe have 2 servers, 1 is the webserver and the other is the Mysql server.
When transfering a 2GB file from the webserver to the Mysql server.
The webserver's connection to the mysql DB server dies completely.
Need to restart the MYSQL process in order for it to come back online.
During this connection downtime, when using phpmyadmin on the mysql server shows no problem running queries etc.
Sent an email by using telnet on port 25 from the terminal. Telnet states my message was sent but I never got it. Is it on the hard disk somewhere. Is there a log file? Where did my email go? Did it go into the ehter? I opened port 25 on my firewall through gnome by selecting 25/smpt checkbox as a trusted service.
View 8 Replies View RelatedTor open port 23 for telnet. Is this normal ?
View 3 Replies View RelatedIn a remote machine port 25 is open its enabled in firewall also...but not able to connect through telnet..why ?
netstat -an | grep 25
Code:
tcp 0 0 0.0.0.0:44525 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
[code]....
Code:
telnet 172.17.65.206 25
Trying 172.17.65.206...
telnet: connect to address 172.17.65.206: No route to host
I have been trying all day today to setup a sendmail SMTP server on our Red Hat 5.5 dev box. We have 2 network cards, 1 to the local network with a 192.168 prefix and an external card which goes out to the web through a BT leased line through a Cisco router.
First I followed one of the many helpful tutorials online to setup sendmail, installed all the required packages and made a couple of small config changes to allow the service to listen on all IP addresses rather than just the localhost 127.0.0.1.
The main change is in the /etc/mail/sendmail.mc file where I have changed the following line;
DAEMON_OPTIONS(`Port=smtp,Addr=x.x.x.x, Name=MTA')dnl
I have tried removing Addr completely, setting to either the local or external IP and then rebuilding the sendmail file using 'make -C /etc/mail' and then restarting using 'service sendmail restart'
The SMTP port has been added into the firewall and it is showing to be listening on IP 0.0.0.0:25 which I believe means it is listening on all IP's assigned to the machine, sendmail is also in listen mode and running correctly.
Finally I have changed the /etc/mail/access file to include the local IP range 192.168 and external IP range and rebuilt this into the /etc/mail/access.db file and then restarted sendmail.
Googling the error all the sites I have found talk about making sure the 'DAEMON_OPTIONS(`Port=smtp,Addr=x.x.x.x, Name=MTA')dnl' line is uncommented and not much else in terms of what else might be incorrect.
I am starting to run out of ideas on things to change or check, telnet works correctly on other ports on the same server, ie httpd for apache on port 80. I have also rebooted the server to make sure that it wasn't something odd happening.
I tried changing the sftpserver port but its not working, besides how can i restrict users from particular ips.Eg: users a can ssh from 192.168.*.*user b can sftp from 200.*.*
View 2 Replies View RelatedI have a server in a colocation environment where I'm allotted 25Mbps. I'd like to avoid exceeding that for obvious reasons. Is there a way I can set the link speed or at least throttle the bandwidth for all services?
View 2 Replies View RelatedI tried to make "ssh tunneling", but failed and got this message.
Quote:
Administrator@windstory-PC /
$ ssh -R 7869:localhost:7869 windowsstudy@192.168.0.4
windowsstudy@192.168.0.4's password:
Warning: remote port forwarding failed for listen port 7869 Last login: Wed Jul 21 01:56:04 2010 from 192.168.0.2 -bash-3.2$
1. system environment
192.168.0.2 - windows 7 + copssh
192.168.0.4 - centos 5.4 x86 + openssh
2. Guide for setting "ssh tunneling"
[URL]
3. Added this to sshd.conf
Quote:
AllowTcpForwarding yes
4. "netstat -na|grep 7869" at 192.168.0.4
Quote:
[root:maestro:~]# netstat -na|grep 7869
tcp 0 0 0.0.0.0:7869 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:7869 127.0.0.1:53539 ESTABLISHED
[code]....
5. result of "ssh -vvv -R 7869:localhost:7869 windowsstudy@192.168.0.4"
Quote:
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
[code]....
6. I added 7869 for telnet service as follow;
Quote:
mytelnet 7869/tcp # My Telnet server
