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.
i make this script to become a service ( i test it from bash, and my script work good), my problem is when i telnet to my local host (127.0.0.1) via a personal port like 5555 telnet give this error: ")syntax error: invalid arithmetic operator (error token is ", i know this error is for echo $(($A+$B)) and i know that telnet can not calculate $A+$B and the error is for this
I'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.
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.
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;
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 have a customer who is complaining that they can connect to prt y on IP x with telnet. They are seeing the following:
telnet x.x.x.x y Trying x.x.x.x... Connected to x.x.x.x. Escape character is '^]'.
after some time the connection of course times out. Connection closed by foreign host. There is no telnet service running on this port so they cannot do anything, but they are complaining tht the fact that telnet "connects" is a security risk. I am having difficulty explaining why they are able to connect with telnet. I know it has to do with the socket layer API in Linux but I am having difficulty explaining this sufficiently. I also can't just say "this is the way linux works" to them. I am looking through "UNIX Network Programming" by W.
I'm trying to capture incoming/outgoing phone call data. Both telnet and nc have allowed me to easily direct this data to a file for later processing, HOWEVER I can't seem to get either to work as a background process. I want to put the connection into a shell script and run from cron.
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.
I hear that it's a bad idea to edit iptables by hand.
I want to open 443. Quote: iptables -A INPUT -p tcp -m tcp --sport 443 -j ACCEPT iptables -A OUTPUT -p tcp -m tcp --dport 443 -j ACCEPT Since I'm not at the box, I can't use the nifty GUI.
from my windows box at work i can only connect to some ports (pop3, telnet, web)also, i can connect to port 1234 (as an example)everything else is blocked.I'm trying to connect with Microsoft Terminal Service Client to my linux box (cant install any vnc)but haven't found a way to make Gnome remote desktop to listen to the port i need (1234).I'm using fedora 13.anyway, i would appreciate any advice on what software to use or hot to configure my Linux box get remote connections from windows box on that certain port.
If I forward port 80 to port 3128 for squid with an iptable rule, does port 3128 have to be open on the firewall or is this all routed behind the firewall?
Made some network and hardware changes, and now I can't get the mailserver to work. It seems that sendmail can't loop to itself on 127.0.0.1. When I nmap localhost, I find that port 25 isn't open.
Naturally, nothing has changed on my system except for different routing, interfaces, etc.
So the question for sendmail gurus,is where should I be looking?
I want to open 177 port of remote server for mypc.com.
Code: -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 177 -s mypc.com -j ACCEPT I wrote this at iptables, but I could not connect mypc.com with remote server.
I want to open port 2700 on my firewall but I don't know how I try with Code:iptables -A INPUT -i eth0 -p tcp --sport 2700 -m state --state ESTABLISHED -j ACCEPT But the port is not open I see the firewall configuration with the command setup . I use CentOS 5.3 here a screen of my configuration :http://upbg.net/out.php/i3537_sshot3.pngCurrently my firewall is off because I don't know how to turn on 2700 when the port is open I will turn on firewall .If I write 2700 in other ports field will 2700 be open ? Before 1 month I try but the port was not open . I have only 1 last question will firewall reduce the load of the my server now mysql use many CPU % and I just don't know why
On my RedHat 9 , I want to open tcp port 4965 but my server does not contain /etc/sysconfig/iptables . Can you please let me know how to open this port?
I heard when running Ubuntu I need to set it to open with one port. I had a friend ran Ubuntu on his laptop at school and had other Ubuntu users at school got access to his computer, is that possible?
I want to open the port 18680 on my remote Fedora 14 machine. I didsudo iptables -I INPUT -p tcp --dport 18680 -m state --state NEW,ESTABLISHED -j ACCEPTsudo iptables -I OUTPUT -p tcp --sport 18680 -m state --state ESTABLISHED -j ACCEPTsudo service iptables saveThe status returned is OK.I have also opened the port on my security group on Amazon. Also, I rebooted the machine.When I use the browser to view the application running at port 18680 the browser cannot connect.
I have system with debian linux installed. i got to know that debian doesent have IPTABLES firewall installed in built. i found the shoerwall firewall installed on system. now i wanted to open port no.7 for application comunication purpose please let me know if any one knows.also one more thing.. if i type command iptables --list i can see list of rules installed on ssytem....confuse which firewall application installed on the system.