A networking program that controls the incoming and outcoming stream of data in a computer.
1
vote
1answer
15 views
Possible sftp connection behind a router that is impossible to open any public ports except some standart ports like http?
I want to ask about the problem that I have with my office computer. I cannot reach the router so I cannot redirect any incoming requests to my PC.
I have to get a huge file from another computer on ...
-2
votes
0answers
26 views
Iptables (easyfwgen) script issues. No internet access
I used the easyfwgen iptables script generator to create a firewall script for my new Mint install. I think all the scripts are in the right place, but I have issues with the rules in the script. I ...
0
votes
0answers
15 views
Firewalld SELinux
Is there any way to better explanation firewall-cmd than the one given in Fedora18 wiki.
I am trying to convert iptables to FirewallD in cmd line without GUI but cannot find a decent example or ...
1
vote
0answers
33 views
PGP keyserver and proxy firewall issues
I am not sure this is a Linux question directly ... I use Arch Linux which uses package signing. This requires me to download a set of pgp keys with the pacman-key program. This works off the ...
-1
votes
1answer
17 views
How to check the ports of Main and dependent Programs [closed]
we can see the ports using the Netstat -tulpn, e.g netstat -tulpn |grep program.
But what is there is program that has multiple modules dependent on main program. How we will know what ports are they ...
3
votes
4answers
72 views
How to check whether firewall opened for a port but not listening on the port
We will be deploying a new application to a Server and the application will be listening on port 8443. We have asked Network team to open the firewall for the port 8443 on that server before deploying ...
1
vote
1answer
44 views
Adblock rule to block g+ / twitter / etc. [closed]
Looks like this rule works to blocking facebook domain, when not visiting the facebook domain (ex.: "like/share" etc. buttons on other pages then facebook):
! don't allow facebook outside facebook..
...
2
votes
1answer
80 views
iptables rules not realoading on CentOS 6.x
I have one single ipset addded to my iptables on a CentOS 6.x box and this rule is lost when the machine reboots.
I have found this answer showing how to make a Ubuntu system reload the iptables ...
2
votes
1answer
62 views
How can I disable UFW logging for a specific event?
My router sends out multicast packets in regular intervals that are blocked by UFW's standard policies. These events are harmless but spam my syslogs and ufwlogs. I can't change the router's behaviour ...
2
votes
3answers
190 views
Linux stack for a home network firewall/proxy?
I've got a generic home 'network' where my ISP supplied modem acts as router with a software firewall built-in. My PCs connect directly to this router to access the Internet.
I want to place a box in ...
1
vote
1answer
82 views
Packet analyzer to intercept and filter incoming traffic before any client app
I am curious if most Linux distros make it possible to intercept incoming network traffic as soon as it enters the system and filter its content based on some rules before any other client can use it ...
2
votes
0answers
90 views
Port Forwarding Between 2 Internet Machines
Here's my scenario:
Setup
There are 3 machines:
A: on the internet : has ip (a.a.a.a), has port pa open
B: my server / gateway : has ip (b.b.b.b), has port pb open
C: on the internet : has ip ...
1
vote
2answers
82 views
Is it possible to whitelist a specific program in iptables?
Is it possible to allow all traffic for a specific program in iptables? Otherwise using nmap and a strict iptables configuration at the same time seems impossible.
0
votes
1answer
14 views
EST/REL or REL/EST in iptables firewall scripts?
-A INPUT -p tcp -m state --state RELATED,ESTABLISHED -j ACCEPT
every Firewall rule usually starts with this.
Q: Does it matter that is it RELATED,ESTABLISHED OR ESTABLISHED,RELATED?
2
votes
3answers
125 views
What does this firewall record mean?
Running iptables -L -n gives me the following info:
Chain IN_ZONE_work_allow (1 references)
target prot opt source destination
ACCEPT tcp -- 0.0.0.0/0 ...
1
vote
1answer
76 views
How to allow access to web only through proxy?
I have a machine with Linux Slackware 13.37. Is it possible to configure iptables, so the users will be able to access web only through squid? The direct access through the browser will be blocked.
...
1
vote
1answer
277 views
Help to understand Iptables Forward chain with DNAT
I have one server where iptables configured with all chains DROP in filter table
eth0 :- 10.0.0.2 [ Intranet assume as LAN ]
eth2 :- 172.16.0.2 [ External clients assume as WAN ]
Now What I am ...
3
votes
0answers
123 views
IPFW Port Forwarding
This is my situation: I want to connect to an OpenVPN server from my office (we're using a proxy, only ports 80 and 443 are allowed).
Server IP address is: 176.31.250.232:843
My static IP address ...
3
votes
1answer
2k views
How to re-enable iptables on Fedora 18?
FirewallD is the default firewall in Fedora 18. I have been using iptables for quite some time and have a custom configuration which I need for logging of ip traffic. I am not used to the new ...
0
votes
0answers
110 views
Migrating a rule from Debian Iptables to PfSense
I have this firewall rule in my (ex) Debian box:
-A POSTROUTING -s ! 192.168.1.0/255.255.255.0 -j MASQUERADE
And I want to implement the same on my pfsense box.
1
vote
2answers
296 views
iptables blocking from internet side on eth1?
How to use iptables to deal with two Ethernet ports?
eth0 port for LAN use (192.168.1.50 Private IP).
eth1 port is connected to the internet via cable modem (80.0.xxx.xxx public IP).
ifconfig ...
0
votes
1answer
71 views
Fedora Firewall no option as of yet
I need a firewall because I was decade long user of internet security suites on windows. I am not a professional of networks or anything but a student who just needs to block unblock running ...
1
vote
1answer
122 views
What to use for firewall testing (port opened or not)
so... we know that we can test that if a port is open on the firewall with:
telnet SERVERIP PORT
..but afaik there are services that can't be tested with telnet, because ex.: telnet doesn't know ...
-1
votes
1answer
79 views
Cyberoam Firewall [closed]
Iam behind a cyberoam firewall in my network which is tracking everything (DAaa usage and IPaddress). Somehow I am able to download torrents, can I be tracked explicitly for downloading torrents using ...
2
votes
1answer
118 views
How to configure OpenBSD pf to only allow inbound from given countries?
I have an OpenBSD 5.2 box what's running a webserver on port 80 and an SSHD server on port 2222.
How can I configure OpenBSD's pf to only allow connections from given countries to port 80 and 2222?
2
votes
1answer
146 views
How to interpret and react to Shorewall log?
I see the following pattern in every 2-3 sec, for several minutes in syslog:
Shorewall:net2fw:DROP:IN=eth0 OUT= MAC=aa:bb:cc:dd:ee:ff:gg:hh:ii:jj:kk:ll:mm:nn SRC=12.34.56.78 DST=98.76.54.32 LEN=60 ...
3
votes
1answer
134 views
Can I limit connections per second for certain UserAgents using UFW?
GoogleBot is hitting my server hard - and even though I have set the CrawlRate in Webmaster Tools it is still hiking up the load on my server and slowing down Apache for the rest of the normal web ...
0
votes
0answers
109 views
fail2ban ignoring ignoreip list
Despite setting the ignoreip value to the IP of our network, it would seem that fail2ban is ignoring this config and still bans us when multiple people access the server via SSH. The ignore list has ...
3
votes
1answer
229 views
How to understand why the packet was considered INVALID by the `iptables`?
I set up some iptables rules so it logs and drops the packets that are INVALID (--state INVALID). Reading the logs how can I understand why the packet was considered invalid? For example, the ...
1
vote
1answer
180 views
Firewall/routing rule in Centos for this setup
I have two ethernet interfaces, namely eth0 and eth1.
I want to implement an advanced routing rule but I am totally new to firewall/routing rules in CentOS.
Here is what I am trying to do:
Both my ...
0
votes
1answer
321 views
Allow incoming connections from Google Translate only
I have a small web server running on port 80, and I'd like to allow only Google Translate to have access to it.
First I tried running dig translate.google.com and dig translate.googleusercontent.com ...
3
votes
3answers
263 views
Can't add large number of rules to iptables
I made a very simple bash script (echo at start, runs commands, echos at end) to add approx 7300 rules to iptables blocking much of China and Russia, however it gets through adding approximately 400 ...
3
votes
1answer
280 views
nmap shows me that one service is “open|filtered” while locally it's “open”, how to open?
I have a Quake 3 server. And it's launched successfully.
The problem is that no one can connect to that server.
I am running: nmap -sU -p 27960 hostname and it's showing me that it's state ...
0
votes
3answers
3k views
How to block https facebook site using iptables [duplicate]
Possible Duplicate:
iptables to block https websites
I am using Zentyal Os as a firewall, it working fine like blocking http sites and but I am not able to block https facebook site.
My ...
1
vote
0answers
68 views
Perform Cisco's DNS Doctoring on FreeBSD
How to perform a change in the DNS response from a DNS server to be a different IP address than the DNS server actually answered for a given name?
...
2
votes
2answers
691 views
MySQL Linux Client Timeout/Keepalive
Is there a way to set a keepalive in the command-line MySQL client on Linux?
Our network recently moved to a VLAN setup, and our systems department no longer has control of the firewall. The ...
4
votes
1answer
942 views
Enable RTSP in iptables
I'd like to receive a RTSP stream via VLC, but when I try to run
sudo -u non_root_user cvlc -vvv -I dummy rtsp://ip:port/x.sdp
I get:
Unable to determine our source address: This computer has an ...
2
votes
1answer
176 views
Make box only communicate on lan only?
I am running a VM with Debian as the guest OS (I can choose another distro). It has nginx running along with some other software.
Some of the software tries to make outgoing connections (for example ...
0
votes
0answers
107 views
Unable to use SIP over VPN, how to find out why
I am doing a VPN access using openvpn utility to connect to my private network. However I cannot use my SIP soft-phone service (which uses a private domain) even if I am connected to that private ...
1
vote
0answers
99 views
What other rules should I use to allow PPTP outbound connection?
I already allowed outbound connection to TCP/UDP port number 1723, but PPTP connection still fail to establish,
If I allow all outbound connection, the tunnel will just go fine.
3
votes
1answer
277 views
How to “jail” a user account's network capabilities on Linux?
Linux box a is connected to a home DSL line with dynamic DNS registration, hosting a tmux session to which multiple clients connect in read-only mode over SSH. All users connect using the same ...
2
votes
1answer
503 views
Changing firewall settings after installation of CentOS via kickstart
I was trying to install CentOS 6.3 via Windows Deployment Server. And to automate the installation process I used kickstart file in which i provided various details required during installation.Then i ...
13
votes
2answers
4k views
How does reverse SSH tunneling work?
As I understand this, firewalls (assuming default settings) deny all incoming traffic that has no prior corresponding outgoing traffic.
Based on Reversing an ssh connection and SSH Tunneling Made ...
3
votes
1answer
1k views
How to configure pfsense to NAT servers?
How can I configure pfsense so it will NAT servers so they can be accessed outside of the company? I tried to play around with the NAT settings, but didn't get anywhere. I want to be able to access ...
2
votes
1answer
275 views
NAT and source IP filtering in PF, using OpenBSD >= 4.7
I just read a book about PF (The Book Of PF, No Starch), but there's one question not answered by it.
If I have a gateway machine using two interfaces, $int_if and $ext_if, and I NAT the packages ...
4
votes
2answers
2k views
What prevents a machine from responding to pings?
I have a CentOS release 5.4 linux box on Amazon EC2 that I'm trying to set up to be monitored via Nagios. The machine is in the same security group as the nagios server, but it seems to be ...
3
votes
1answer
647 views
Is berkeley packet filter ported to linux?
I am doing some research to figure out what distro's of linux contain kernel packet filtering and are compatible with BPF.
http://kernelnewbies.org/Linux_3.0
http://lwn.net/Articles/437981/
These ...
1
vote
1answer
706 views
Redirect http using iptables for an ip range
I have a range of ip addresses (10.13.13.10-19) that I want to redirect all outgoing http traffic to an internal webserver. So if someone in that range tried to access any site, the html from my ...
2
votes
2answers
247 views
How to Add rules to IP Filter (Firewall in SCO)
I now have a headache trying to figure and Google how to add rules to the firewall in SCO. I know I have done it before, but I forgot to document it.
I have had a look in the SCO OSR600 Documentation ...
1
vote
2answers
211 views
How to allow mysql remote connections via particular interface
I have a 10.237.49.251 IP on eth0 and another IP on another interface
How do I enable remote mysql calls on eth0 device?
