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).
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 a server on my router on the DMZ. All outside traffic goes to it. This server has Apache running and the domain mysite.com resolves to the the DMZ web server. I have a second server on the LAN that also has apache running. I want to set up another domain, myothersite.com to resolve to the second server on the LAN. Since the main server is on DMZ I have the DNS A records for myothersite.com pointing to the public IP that the DMZ is on.
How do I get myothersite.com to resolve to the second webserver on the LAN? What configuration do I need to do on my DMZ server so it routes traffic for myothersite.com to the other server on teh LAN? Do I use BIND DNS? If so please advise on how to set that up. BIND DNS seems confusing and I having trouble knowing how to configuring it. Is there another option besides BIND?
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?
So what I want to do is setup a gateway(or router, idk what Ubuntu refers to it as.). So my set up would be Modem>Server>Switch>Router. I know that I need to set up it up as a DHCP server as well. I would also like to setup it up as a firewall too. I already have two Gbit cards that are already configured. So how do I do this? I already tried one tutorial, but it was old and was for Debian. I also installed ebox, but I couldnt figure that out either.
I set up debtorrent on all my machines on my LAN, which is a varied mix of machines, including one Karmic, one Lucid, and a Debian Squeeze. These are behind a NAT-based firewall. I'm not sure if I'm getting any benefits from the bittorrent peer-to-peer features because I am not forwarding any ports.
Does anyone have a similar configuration? How does one deal with debtorrent on multiple machines? Does it really help if ports are forwarded? If forwarding helps, does one need to segment the forwarded ports for each different machine?
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:
I 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?
i 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
Which 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
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.
I 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?
Just setup an ssh server...kinda. I need to forward the port (22) through my router. I have forwarded ports before for programs so the whole thing isnt a mystery. But i need to know what to put in for a couple boxes.... Private ip: ? protocol type: tcp, udp, or both?
I'm trying to make my wireless router always give me the same ip address every boot (192.168.1.100). I do not have a static ip address from my isp.
Everything I've tried from online help has made my internet break and I'm not even sure what exactly I should be searching for on google.
Ultimately, I'm trying to get my wireless router to forward ftp requests to my computer which shares the network with an xp machine. I think this is the way to go about it.
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.
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.
Small 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"
I 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?
I 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
World of Warcraft requires that TCP Ports 1119, 1120 and 3724 are forwarded. The Blizzard Downloader requires that TCP ports 3724, 1119, 4000, 6112, 6113 and 6114 are forwarded. It can also benefit from having ports 6881 through 6999 forwarded. The World of Warcraft Voice Chat feature uses UDP Port 3724.
i use the hotspot feature to play warcraft and i am running ubuntu 10.10 ... i need to forward these ports ... any way to easily download an app to configure the phone like you would a router? its probably easy i just cant find it.
i 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)
