Ubuntu Servers :: Find Port Names For Iptables?
Jun 4, 2010I noticed you can use names for ports like ssh, instead of the actual port number in iptables, but I can't find a list of what they are?
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Ubuntu Servers :: Connection On Port 143 - Iptables Are Open?
Feb 2, 2010I am configuring an internal only IMAP server for archival emails. I am absolutely baffled why my connection is being refused. UFW is disabled and IPTABLES has a rule to allow all connections on 143 and 993. When I telnet this response is given:
Code:
telnet localhost 143
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused
Even nmap shows the port closed. Here is my iptables rule:
HTML Code:
-A ufw-user-input -p udp -m udp --dport 143 -j ACCEPT
Ubuntu Servers :: Port Forwarding Setup Using IPTables - Transparent Proxy
May 13, 2010I'm new to linux, but enjoy using it very much, especially without a GUI, console is fun! I need to set up port forwarding. We have 3 servers, 1x running Ubuntu server 8.04 (used as transparent proxy), 1x server 2003, 1x windows xp.
The linux box has the following ips:
eth0 (internal) 192.168.1.5
eth1 (external) 192.168.0.7
Windows server 2003:
192.168.1.6
Windows XP:
192.168.1.9
Router:
192.168.0.1
The router automatically forwards specific ports to 196.168.0.7 (Linux eth0). From there I want to forward port 8585 to 192.168.1.6 and 3000 to 192.168.1.9. Is there a way that I can do this using iptables?
The commands that I think I'm gonna use look like this:
iptables -A FORWARD -s 192.168.0.0/24 -p tcp --dport 8585 -d 192.168.1.6 -j ACCEPT
iptables -A FORWARD -s 192.168.0.0/24 -p tcp --dport 3000 -d 192.168.1.9 -j ACCEPT
Would this be a correct way of doing it? My biggest problem is that I can't test it without going live, and if I go live and something doesn't work, the entire building will be left without internet, people will hate me. Also, The proxy captures all data on port 80 and forwards it to 3128 so that the proxy can monitor the usage, and a few systems runs fine with it, others however can ping websites, and internet explorer says "website found, waiting for reply" but the webpages cannot be displayed.
Ubuntu Servers :: Port 21 Reported Open By Nmap And Netcat, But Blocked By Iptables?
Oct 11, 2010Strange issue here when trying to verify firewall on Server 8.04. No ftp service running at all on server, but both nmap and netcat report port 21 as being open, even though it isn't.I am 100% sure that port 21 is not actually accessible and iptables rules are fine. Trying to connect to the port fails, yet nmap and netcat seem to report a "false positive"?Have also checked on a number of other servers I'm running, and this "false positive" seems to apply to all of them.
View 1 Replies View RelatedUbuntu Servers :: Find Out What Is Using Port 80?
Aug 9, 2011I have an Ubuntu 11.04 server with lighttpd installed as my web server. It was working fine, but now when I restart it it gives me the following error...
"can't bind to port: 80 Address already in use"
Is there a way for me to find out what is using port 80 in it's place?
Security :: Iptables: Verify Traffic On Port To Check If It Is Legitimate For That Port?
Apr 18, 2011Is there any way to verify if packets being trafficked over a certain port are valid for the service you want to use this port for?
One obvious example that probably clarifies my question:
When I open port 443 (outgoing or incoming) for https/ssl traffic, I don't want this port to be used for say openvpn traffic.
Thus: when someone wants to surf to a website with https, it should be ok but if someone wants to connect to his home openvpn server over that same port, it should be blocked.
Networking :: Use Iptables In Order To Forward All The Incoming Packets For Port 5555 To Port 5556?
Apr 4, 2011I'm trying to use iptables in order to forward all the incoming packets for port 5555 to port 5556 on the same server (192.168.2.101).
I wrote the following commands:
iptables -A PREROUTING -t nat -i any -p tcp --dport 5555 -j DNAT --to 192.168.2.101:5556
iptables -A FORWARD -p tcp -m state --state NEW -d 192.168.2.101 --dport 5556 -j ACCEPT
Networking :: Iptables Can't Port Forward (PAT Port Address Translation)?
Feb 20, 2010I'm using a Debian servers, as router/firwall.. I've two ethernet interfaces into the server, one for wan and one for lan. The i use SNAT so my LAN clients can access the internet throgh the debian router. That is working... Now i want to be able to access servers on the LAN site from the WAN site, and i wanna use port address translation (PAT). I have a FTP server running on a lan server, so i'm trying to portward port 21.
iptables -t nat -A PREROUTING -p tcp -i eth1 -d (WANIP) --dport 21 -j DNAT --to 192.168.1.2:21
When people try to access my FTP from the WAN site, they are redirected to the local FTP server, and they are promted for crendentials, but when the credentials are typed, and the local ftp server should answer the wan request, the connections dies.
The wan clients are being promted for credentials, so they are redirected to the local lan server, but after that the connections dies, so i think there is some kind of nat problem, when the local lan server is trying to respond to the wan request..
Here i my iptables script:
#flush table
iptables -F
#input regler
[code]....
Server :: If Forward A Port In Iptables, Does The Port Have To Be Open On The Firewall
Aug 5, 2009If 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?
View 4 Replies View RelatedNetworking :: Iptables - Port Forwarding To Blocked Port?
Mar 25, 2010I have a mail server on which I would like to block port 25 on my eth0 for everyone except our external spam filter. the problem is that I want our users to be able to connect via port 10025 which is forwarded to port 25, which then is blocked...
View 2 Replies View RelatedUbuntu Servers :: Setup Iptables Rules In /etc/if-up.d/iptables?
Apr 16, 2011I am running Ubuntu server 10.10 and trying to setup iptables rules in /etc/if-up.d/iptables
Quote:
root@host# cat /etc/network/if-up.d/iptables
#!/bin/sh -e
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
Problem is that iptables doesn't get updated and I don't see them when iptables -L is executed after reboot.
Ubuntu Servers :: Just Installed Ubuntu 9.10 - But Port 80 Blocked - Can Not Find Server/location
Apr 12, 2010I installed Ubuntu 9.10 and tomcat 6 java servlet container. I am trying to run the tomcat server on port 80, so I edited tomcat's configuration file (server.xml) and changed the default port from "8080" to "80". I launched tomcat server, went to my browser and entered:[url], but it says can not find server/location. Then I edit the server.xml and revert back to port "8080" and then enter: [url] and everything works fine. So my guess is some other service is taking up port 80, but I would think not, since I just installed Ubuntu and made sure apache isn't installed or running.
So I went to "System" --> "Administration", then choose "Network Tools". I then executed Netstat and did not see anything taking up port 80, but I do see port 8080 taken (assuming it is the tomcat server). Then I also did a Port Scan and entered my IP number. Again, I don't see port 80 taken, but do see 8080 being used.
I had a winxp laptop computer behind home wireless and was running tomcat 6 server fine with it, but it over-heated and died recently. So I got a used laptop and just installed Ubuntu 9.10. I have not changed my wireless router settings. It is the same as before. So I have ruled out my home's hardware/network equipment.
So here now I sit, wondering what is up?
For security reasons, is port 80 initially blocked by Ubuntu for some reason? Is there something I have to do beforehand to free up port 80?
Fedora Servers :: Unable To Restore My Iptables From Iptables-save After Upgrading
Nov 26, 2010I am unable to restore my iptables from iptables-save after upgrading Fedora. I cannot get iptables-restore to work, and I have resorted to entering rules manually using the GUI.
View 2 Replies View RelatedNetworking :: Can Eth Device Names Be Correlated To Physical Port?
Dec 1, 2009I am building a custom RedHat+<our-software> installer iso for our own appliance. I am using Red Hat 5.4. The appliances has two on-board eth interfaces. On the back panel of the appliance, these ports are marked 1 and 2. When I install RH, I find the device names assigned such as eth0/eth1 are arbitrary. I understand this is to be expected with kernels 2.6+. Most of our customers connect their eth cables to the port marked 1 on the back and assume they should configure eth0 to make the device reachable. However, sometimes port 1 gets assigned "eth1". This is not a blocking issue, but its going to confuse our customers and we wanted to make it easier on them.
From reading online discussion boards, I know HOW to switch the assignment of the eth names. However, what I am do not know is whether I need to switch them at all. So I have two questions
1) Is there anyway for me to tell which eth mac corresponds to which port on the back? Since they are soldered on the motherboard and not movable, I would think there would be some way to figure out that x mac address corresponds to the upper port (marked '1' etc).
2) Is there a way to tell this by running a linux command? We need to do this automatically so I need to be able to figure it out at install time from the kickstart post-install or similar.
Ubuntu Security :: Iptables Port 25 Is Open
Feb 28, 2011I've recently installed 10.10 server edition, and I must say it was a pleasant suprise, it's just the way I like it. I use it as a squeezebox-server. But I've run into a problem with the firewall. I did a portscan, which told me there are more ports open then I've told UFW to open. Among which port 25 and 119, when I telnet from another PC to those ports, the connection gets accepted, although there is no answer to any commands (as expected, there's no mail server running). Iptables print-outs also don't mention anything about the respective ports or a daemon that could be responsable, and the same applies to "ps -e" or "ps aux".
Iptables seems to be working, when I remove the rules to allow samba to work, I can't reach the shares, and when I insert them again I can reach the shares. "sudo ufw deny from any" as last rule doesn't change anything either (deny incoming is default (although I never issued the command "ufw status verbose" says it is) so it shouldn't, but ports 25 and 119 shouldn't be open either).
Ubuntu :: Port Forwarding Using Iptables Not Working?
Jul 17, 2009I am using ubuntu 8.40 as a router wit 2 nic.eth0 is for local and eth1 is for external network.i have a internal webserver in my lan and want to forward some ports to the net and i executed te following commands.
iptables -t nat -A PREROUTING -p tcp -i eth1 -d 192.168.0.239 --dport 8080 -j DNAT --to 192.168.10.99:8080
iptables -A FORWARD -p tcp -i eth1 -d 192.168.10.99 --dport 8080 -j ACCEPT
But i cant connect to the port 8080 from the external network.
Networking :: Iptables Port 161 UDP/TCP?
Mar 18, 2011iptables -A INPUT -p udp --dport -j ACCEPT
iptables -A INPUT -p tcp --dport -j ACCEPT
iptables -A FORWARD -p udp --dport -j ACCEPT
iptables -A FORWARD -p tcp --dport -j ACCEPT
and the rules are placed in iptables, i can see them when I do iptables -L. But when I do netstat -an | grep 161 I can see that port 161 (SNMP) is not listening. Why?
Ubuntu Networking :: Port Forwarding With Arno Iptables?
Feb 20, 2010iam using arno iptables can give me command to ip forwarding cause my web server behind my router. my ip web server 192.168.0.11 and my ip router on eth 1 192.168.0.1 and eth0 i use to dial up my modem and i use pppoe for that.
View 2 Replies View RelatedUbuntu Networking :: Using Iptables To Change A Destination Port But Keep The Ip The Same?
Mar 23, 2010I am playing around with transparent proxies, The current way I am doing things is the program makes a request to a computer on port 80, I use
Code:
iptables -t nat -A OUTPUT -p tcp --destination-port 80 -j REDIRECT --to-port 1234 to redirect to my proxy that I am playing with. the proxy will send out a request to port 81 (as all outbound port 80 are being fed back in to the proxy) so I want to do something like
Code:
iptables -t nat -A OUTPUT -p tcp --destination-port 81 -j DNAT --to-destination xxxx:80 The problem lies with the xxxx part. How do I change the destination port without changing changing the destination ip? Or am I doing this setup completely wrong,
Ubuntu Security :: Iptables Not Allowing Port Forwarding
Sep 5, 2010I've got two virtual machines running, the first VM (VM1) has two network interfaces, one bridged with my real lan, one a private subnet. The second VM (VM2) has one nic, only on the private subnet.
I have VM1 acting as a router for VM2, giving access to my real lan for internet access. The problem I'm having is I cannot get VM1 to forward ports 80 (http) or 222 (ssh) to VM2 from my real lan.
Here is the script I've cobbled together from various (foreshadowing!) locations:
Code:
Ubuntu Networking :: IPTables Now Showing Port Open?
Sep 22, 2010I am getting the hang of IPTables.I've setup to open certain UDP ports but they simply refuse to show when I iptables -L.
iptables file:
$IPT -A INPUT -p udp --dport 13000 -j ACCEPT
$IPT -A INPUT -p udp --dport 13001 -j ACCEPT
[code]....
Ubuntu Networking :: IPTables / Masquerading - Port 80 And 3128
Nov 17, 2010I am fairly new to Ubuntu/Linux and I have somehow managed to get a server up and running. For the past few months I have been trying to get masquerading working.
I have 2 network cards
eth0=Internal Lan IP address 192.168.0.254
eth1=router External IP address 10.0.0.1
I want all my internal lan traffic to go through my linux box & only have port 80 & 3128 go through squid. So for all pop3/smtp action I want the linux machine to act like a router & for port 80 & 3128 I want it to go through squid.
Ubuntu Networking :: Iptables And Cannot Get Port Forwarding To Work?
Mar 8, 2011I've been beating myself over the head with iptables and CANNOT get port forwarding to work. Here's my situation: Static LAN IP on eth0 Static internet IP on eth1 ip_forward is turned on by uncommenting in sysctl.conf Here's the output of iptables-save:
Code:
# Generated by iptables-save v1.4.4 on Tue Mar 8 10:34:12 2011
*nat
:PREROUTING ACCEPT [2443:347058]
[Code]...
Edit: by the way, the intended purpose of this machine is to server as a gateway and firewall. MASQUERADE is working, for whatever that is worth. And the host behind the firewall that is serving up http is definitely working too. All that is not working is getting hosts on the internet talking to hosts behind the firewall.
Ubuntu Networking :: Port Open In Iptables But Nothing In Netstat?
May 16, 2011I need the port 27015 to be open. I've opened it in iptables :
Quote:
iptables -A INPUT -p tcp -i eth0 --dport 27015 -j
But when i try :
Quote:
netstat -nan
The port 27015 do not appear as "LISTEN".
Ubuntu Security :: Iptables, Block Port Except For Eth0
May 24, 2011I would like to allow incoming and outgoing connections when I'm connected to a wired connection, but drop it otherwise. I noticed that ufw can't block outgoing traffic because of will I give iptables a try. I'm unsure if dropping packages that are outgoing will work, the rule after the block rule will allow all outgoing connections.
This what the rules are intended to do, unsure if that is actually the case. Allow all loopback traffic. Allow ping replys Allow incoming on port 12345 if eth0, deny otherwise. Allow outgoing on port 12346 if eth0, deny otherwise.
Code:
iptables -A FORWARD -j DROP
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -p icmp --icmp-type 0 -s -m state --state ESTABLISHED,RELATED -j ACCEPT
[Code]....
Networking :: Iptables To Hide A Port?
Jan 13, 2010I am running a voip server on port 5060. I want to hide this to all the robots scanning the net permanently - I know this is not enough security - it is just to prevent them from wasting by bandwidth testing all usernames until fail2ban stops them !
I'd like to have port 5060 accepting requests only from 'trusted' hosts, while others (client with dynamic ip) use port 5065 - thus, port 5060 will only appear open for some trusted partners and the bots will skip to something else.
I have setup the iptables rules succesfully to accept only trusted hosts.
-A RH-Firewall-1-INPUT -s 93.x.y.z -p udp -m state --state NEW -m udp --dport 5060 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp -m state --state NEW -m udp --dport 5060 -j DROP
I've added a PREROUTING NAT rule that change the port from 5065 to 5060 for others - but then, this gets caught in the INPUT rule as port 5060 -A PREROUTING -p udp -m udp --dport 5065 -j DNAT --to-destination 192.168.1.1:5060
This works so well that the packets coming on port 5065 are translated to port 5060 and get caught in the DROP rule...
Red Hat / Fedora :: IPTables In Part Of SSH (Port 22)
Jun 1, 2011I have blocked all connection with iptables and allowed only the loopback:
iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
iptables -P INPUT DROP
iptables -P OUTPUT DROP
iptables -P FORWARD DROP
Next I want to allow only ssh connections, and also I want to record the IP address of each attempt to access port 22 using the recent module. Then I want to to see if that IP address has attempted to connect 2 or more times within the last 60 seconds, and if not then the packet is accepted:
iptables -A INPUT -p tcp --dport 22 -m recent --set --name ssh --rsource
iptables -A INPUT -p tcp --dport 22 -m recent ! --rcheck --seconds 60 --hitcount 2 --name ssh --rsource -j ACCEPT
iptables -A OUTPUT -p tcp --sport 22 -j ACCEPT
iptables -A OUTPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -p tcp --sport 22 -j ACCEPT
iptables -A INPUT -j DROP
iptables -A OUTPUT -j DROP
General :: Blocked SSH 22 Port With IPtables?
Jan 20, 2010I get today a server with CentOS.. and someone told me to block access to port 22 for all IP's except my.. so I did
Code:
iptables -A INPUT -p tcp -s my_ip --dport 22 -j ACCEPT
and after
[code]...
Networking :: Iptables Not Port Forwarding?
Aug 14, 2010I have a CentOS box which is Internet Facing. It has 3 LAN's connected to it which are for virtual machines.
I want to port forward port 445 to a machine on one of the LAN interfaces. I have tried various ways to get it done, but still cannot access that port from the interface. I definately know device hosting port 445 is live, as I can ping it from the CentOS box and use lynx to access it! (It's a web server)
iptables -t nat -A PREROUTING -i eth0 -p tcp -m tcp --dport 445 -j DNAT --to-destination 192.168.0.2:445
Networking :: Iptables Port Forwarding?
Jun 7, 2010I've been Googling about port forwarding iptables and even though there's result and I've applied it in my script, I can't make iptables forwading request to another machine so I decided to ask help.
eth0 is my Internet Interface (1.2.3.4 is the public ip)
eth1 is my Lan Interface
eth2 is my DMZ Interface
[code]....