I am having trouble getting ports to open, on the router that the server is connected to it is set to DMZ, so everything passing through the router should go to the server right? but when I use a port checker none of the ports that I need to be open are. so my question is does ubuntu have a built in firewall that no one told me about? or something that would block me from having the ports open?
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I have just switched over from firestart to gufw.I have set all incoming traffic to deny and all outgoing traffic to allow.I have rules set for incoming traffic, and have only opened 1 port on my system for torrents. My router also only has the same port opened which again is for torrents.I use "Network Tools" which is included on squeeze and do a portscan of 192.168.1.100 and 127.0.0.1 I get all kinds of crazy ports coming back as opened. What is even stranger is if I do a few scans, these ports change, so one port on one scan may come up as open, then it will disappear and a different port may show as open.
Mind you none but the torrent port is forwarded in my router, I have no idea what any of these other ports are, or why they are even showing up.What the heck is going on? I dont think this is normal? Am I at any higher risk for attack?
how to open firewall ports without using yast. The reason I'm asking is because I'm working on a .sh script for the installation of a couple of programs. Some ports need to be open for the programs to work, I find it really annoying to go to yast and type the ports manually every time. I've looked at /etc/sysconfig/SuSEfirewall2 but can't seem to find anything, I also know that after the changes I will have to stop start the firewall by running:
SuSEfirewall2 stop
SuSEfirewall2 start
I have a couple of openSUSE 11.2 machines and each is directly connected to the Internet (they are not behind a router, firewall, etc). I want them to be able to communicate without any firewall restrictions, but keep the firewall rules for all other IP addresses. Is this possible? the software package I'm trying to use randomly chooses a port to use in the range of 32768-61000 and I don't feel comfortable having a port range that wide open on both machines.
View 5 Replies View RelatedI would like to ask today how to open up specific ports in Linux firewall (iptables). Recently I have changed the SSH port in server from 22 to 30022 by typing
Code:
# vi /etc/ssh/sshd_config
Code:
Port 30022
"/etc/ssh/sshd_config" 111L, 3027C
And then for the iptables configuration file:
Code:
# vi /etc/sysconfig/iptables
[code]....
How to configure the iptables properly so that my Windows PC can access the Linux with port 30022?
I am trying to understand why when running nmap against a SonicWALL firewall at a remote location, the SonicWall firewall is saying that most of its 65535 ports are open? I know this cant be correct and remember reading about how some of these network appliances are setup this way to thwart off attacks.
View 7 Replies View RelatedI have a question about /etc/services file. If I open ports in firewall, do I need to alter /etc/services file in order for certain apps to work?
kpasswd 464/tcp # kpasswd
kpasswd 464/udp # kpasswd
# Theodore Ts'o <tytso&MIT.EDU>
# 465 is illegal used by eMail Server
smtps 465/tcp # eMail Server
#urd 465/tcp # URL Rendesvous Directory for SSM
igmpv3lite 465/udp # IGMP over UDP for SSM
# Toerless Eckert <eckert&cisco.com>
digital-vrc 466/tcp # digital-vrc
digital-vrc 466/udp # digital-vrc
Above example shows if 465 tcp isn't altered, Postfix MTA fails to listen on 465 tcp port. What if there's a bigger span 3000:7000 TCP/UDP, is there a need to alter each line by hand?
How do I open ports 5198/udp and 5199/udp on a slackware based firewall?
View 2 Replies View RelatedI now have a firewall up and running: almost perfectly. When I use nmap and perform the most comprehensive scan I can think of, it cannot detect any wide open ports (unless bittorent is running) and cannot fingerprint the OS. My last 2 questions about my firewall (I am very happy now) are:
It seems as though Firestarter has been "abandoned" by the developers, and that gufw is more current. Does it really matter which firewall I use because don't they all do the same thing? I like firestarters system tray icon a lot. 2nd question is I have two open|filtered ports. Are these still pretty well protected?
It is very pleasing to see that I have no open ports, because if you were an experienced Windows user like I was, you got used to the fact you were going to have open ports no matter what. Linux's builtin firewall completely destroys the expensive and useless scams they call Norton and McAfee. Linux officially rocks now
Within the documentation of example OpenVPN setups there is a setup that shows an OpenVPN Server with two network interfaces. One interfaces is plugged into the public internet network and the second interface is plugged into the private network.
Normally I assume that it would be best to place the OpenVPN system inside the network behind the router and firewall and open only the ports needed on the router to allow access to the OpenVPN system. All other router ports would be closed. This is the first example they show. To see what I am talking about see page(s) 6-7 here -> [URL]
If one were to use the two interface public facing setup, when would that setup best be justified? I guess if you didn't want to open any ports on the router/firewall then this could be justified but then you have to lock down this public system individually instead of having it protected by the network firewall.
I have linux server setup on a network with 2 interfaces. One (eth0) is connected to the regular network and the other (eth1) has a DHCP server and transparent web cache listening on it. The machines connected on the eth1 side are on a different subnet and the linux server is there gateway. Untrusted machines are introduced to this network to keep them isolated.
This isolation works well, too well. There are a small set of resources on the regular network I would like to make available to machines on untrustworthy network. I think I need to use iptables but alas I've had no luck in piecing together the command I need (in one case looking myself out and having to physically reset the machine).
How to open RTP UDP ports (port_number : port_number) in openSUSE 11.2 firewall with yast?
View 2 Replies View RelatedI'm encountering a strange problem. I need to open and forward all UDP and TCP ports related to VoIPtelephony (5000:32000) in the Suse 11.1 server that's acting as router/firewall in our setup. The ports must redirect to a Asterisk server in the local network. (This server has the IP adress 192.168.0.3)I've opened ports in Yast (Firewall>Ports>Advanced) and putted in some masquerading rulesirewall>Masquerading):0/0,192.168.0.3,tcp,5000:31000,5000:310000/0,192.168.0.3,udp,5000:31000,5000:31000when I do a nmap localhost I get:Starting Nmap 4.75 at 2010-01-08 16:52 CETInteresting ports on localhost (127.0.0.1):
Not shown: 991 closed ports
PORT STATE SERVICE
21/tcp open ftp
[code]....
"Ubuntu Server has no open ports by default" - [URL]. Does this mean right after a 10.04 Server Edition installation, if a user wants to start a web service e.g. a Java process to listen on say port 8080, he would have to configure the firewall first?
View 1 Replies View RelatedI've been struggling for days trying to open port 53 and 25 but can't get it to work. My iptables at /etc/sysconfig contains the following:
# Firewall configuration written by system-config-firewall
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0] .....
On the server machine when I do port scan with nmap I see the following result:
Starting Nmap 4.76 [URL] at 2010-03-28 01:03 CET
Warning: Hostname localhost resolves to 2 IPs. Using 127.0.0.1.
Interesting ports on localhost (127.0.0.1):
Not shown: 986 closed ports .....
But when I try to do telnet from an external machine, e.g:
telnet <IP of host> 53
I get:
Connection refused
telnet: Unable to connect to remote host
I also did a port scan with a tool on an external machine but port 53 and 25 weren't listed as opened ports. Also CheckDNS.net on the server returns "Connection reset. Probably DNS server is offline". I am 100% sure that named and sendmail are running. When I do a ps -aux I see:
named 9261 0.0 0.3 85528 14784 ? Ssl 00:46 0:00 /usr/sbin/named -u named
root 2550 0.0 0.0 9536 1960 ? Ss Mar23 0:02 sendmail: accepting connections
I've tried to set up a Hadoop cluster on a few freshly-installed 10.04 Server Edition machines and hit a problem. (I was able to set up the cluster using Desktop edition previously). The issue is that I can't connect to the service even though the Java process is running and listening on the port and there is no error in the logs. Anyway, I started to wonder if it was firewall issue so I googled it and found conflicting information.
1. "Ubuntu Server has no open ports by default" - [URL]
2. iptables shows different info. ufw is also disabled.
hadoopadmin@machine-1:~$ sudo iptables -L
[sudo] password for hadoopadmin:
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
hadoopadmin@machine-1:~$ sudo ufw status verbose
Status: inactive
I even tried to enable ufw and did "sudo ufw default allow incoming" but still no help. The only package I manually selected during installation is OpenSSH server.
I have a JavaCL program trying to open a port on 41xxx and it is getting permission denied unless I run it as root. I would like to grant a single user this permission for opening this port. This program runs fine on a vanilla ubuntu install but not on server. Where does Ubuntu handle user permissions for opening ports?I understand this is typically a no-no on a server but this is an unusual circumstance.
View 1 Replies View RelatedI have ordered a server with OS:
Ubuntu Server 11.04
After a quick nmap scan I found out a few open ports. What is using these ports?
1102/tcp filtered adobeserver-1
1201/tcp open nucleus-sand
In my firewall I have these ports open:
21
143
110
[code]...
What are the security implications of closed ports?
View 5 Replies View RelatedI want to lock down my server to allow only certain ip addresses and ports in. I was thinking of doing this through the iptables but someone sugguested I used the hosts.allow and deny files to allow who can access the system. What do people suggest? If I"m trying to ensure no ip's can access my system except the ones I want, how would I do this with just the allow and deny files?
View 4 Replies View RelatedI want to know how to add (ports to open)in firewall using command or scriptor any ather method
View 4 Replies View Relatedi need to add some ports in firewall(RHEL5) how can i do it using command or script or anything?? i know one method from graphic firewall wizzardtell me other shortcut to add more then one ports
View 2 Replies View RelatedWhich ports should be open for a mail server for INPUT CHAIN? When I use firewall rules (allow just a few ports), some users complain that they're not receiving messages from other domains. When the firewall is disabled these ports show as open:
Code:
Not shown: 9987 closed ports
PORT STATE SERVICE
21/tcp open ftp
[code]....
Which ports should be enabled?
I'm using opensuse 11.3 32bit with LXDE. I have configured an apache tomcat server listening on port 8080. Yast was used to open udp 8080 and tcp 8080 in the firewall by manual entry under the advanced button of 'allowed services' menu.Another system was used to access the tomcat server via a firefox webbrowser. The attempt was unsuccessful. The url used was [URL]. firefox webbrowser keeps showing'connecting ...' until timeout. I'm assuming that inspite of the specified port openings in the firewall, it is somehow ignored. If I were to disable the firewall, then I can access the tomcat server with the firefox webbrowser.
View 2 Replies View RelatedSmall server running 5.3 - stock postfix configured to use Maildir. Dovecot configured but both pop and imap ports blocked by firewall. Access to mail is via Squirrelmail via https. Configured to virus scan via ClamAV. Works just fine. Now I want to add procmail filtering. So I create these two files - ~/.forward and ~/.procmailrc in my user home dir: "|exec /usr/bin/procmail -f- || exit 75 #mpeters"
View 1 Replies View Relatedi have two questions and thought that anyone here could have the answers.first things first,i want to make firewall accept a range of ports (say 8000:9000) because im using mpd process manager to make some parallel processing, does anyone know the command that satisfy this?
the second thing is, when i open a range of ports like that, it would put my system at risk if some bad guys somehow identifies this range, is there is anything that solves that matter(i.e. makes the firewall monitor the packet, if its an mpd accept if not drop)
I am running apache2 and tornado web servers on the same server with one ip address.
The apache2 listens on port 80. Tornado listens on port 8888. I want to redirect requests from a specific ip port 80 to port 8888. I don't have the ability to change the port request on the device. It wants is looking for a web server on port 80.
Any other web server request should go to the apache.
I tried adding the following to /etc/ufw/before.rules
When I run iptables -L it doesn't appear. I have disabled and enabled ufw with no help.
A few months ago I installed Ubuntu 9.10 on my girlfriends laptop, on her request, as she didn't like Windows any more. Since then the internet connection periodically slows down due to too many open ports/connections. Always when this happens I call our ISP and usually there are around 80-200(!) active connections to various IP's.
She is not downloading torrents or anything.
She only uses Firefox and a few open tabs as people do.
Skype is open.
Wireless internet connection.
I am thinking either Ubuntu is updating more or less constantly or the ports/connections aren't closed "after use".
I'm locking down my laptop. I know I can use a firewall to ensure nothing gets through that I didn't catch, and I certainly plan on using one, but in the meantime, I want to know what exactly is running on my system.
nmap localhost returns:
Code:
james@james-linux:~$ nmap localhost
Starting Nmap 5.00 ( http://nmap.org ) at 2010-07-26 23:33 CDT
Warning: Hostname localhost resolves to 2 IPs. Using 127.0.0.1.
Interesting ports on localhost (127.0.0.1):
Not shown: 994 closed ports
PORT STATE SERVICE
25/tcp open smtp
111/tcp open rpcbind
139/tcp open netbios-ssn
445/tcp open microsoft-ds
631/tcp open ipp
2049/tcp open nfs
Nmap done: 1 IP address (1 host up) scanned in 0.18 seconds
However, I know that localhost goes back to the loopback interface, 127.0.0.1. So, to see what was really open, I ran nmap 192.168.0.108, which is my laptop's IP at the moment.
Code:
james@james-linux:~$ nmap 192.168.0.108
Starting Nmap 5.00 ( http://nmap.org ) at 2010-07-26 23:33 CDT
Interesting ports on 192.168.0.108:
Not shown: 996 closed ports
PORT STATE SERVICE
111/tcp open rpcbind
139/tcp open netbios-ssn
445/tcp open microsoft-ds
2049/tcp open nfs
Nmap done: 1 IP address (1 host up) scanned in 0.14 seconds
Now if I understand correctly, I can attribute 139 and 445 to my Samba share. That I'm okay with. What I don't know is 111 and 2049. Does anyone know what these ports are, what's running on them, and how I could turn them off, supposing that they are a security risk?
