A Firewall is an application or hardware device used to inspect and filter network traffic.

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Advice for configuring a SonicWALL NSA 2400 to use two subnets and L2 Bridge Mode

This post is not an exact duplicate of How to configure remote access to multiple subnets behind a SonicWALL NSA 2400 . However, I am having this problem, almost verbatim. Unfortunately, we even have ...
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1answer
1k views

Allow access to printer between interfaces on Cisco ASA5510

I have a Cisco ASA5510 where we have to separate networks on two separate interfaces. The networks should have nothing to do with each other except that network B needs to access a printer on network ...
2
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2answers
3k views

Configuring Fortigate OS4 for FTPS

I configured iis7 ftp to allow ssl connections. I set the ssl firewall to use ports 50000-50050. If I set up a custom service on my fortigate firewall for ftps with source ports 990-50050 and ...
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2answers
1k views

Access print server through firewall?

At my workplace, we have two fiber networks setup, one for the business network and the other for process control (industrial manufacturing). On the business network, there is a standard print server ...
2
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2answers
1k views

Cisco ASA 5505 Config

I have looked through a lot of these posts on the Cisco ASA5505 as well as gone online. I am looking for some straight forward step by step instructions to complete the following tasks. I know how to ...
0
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1answer
18 views

Web app architecture - firewall blocking

I'm currently working on a web app and seem to be having a few problems with the app being blocked by office firewalls of our test groups. My background is in design / front end so my knowledge of ...
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0answers
8 views

Sonicwall seems to be blocking port 3690 on random internal up address

We are trying to connect to a clients subversion server over the internet using port 3690 and random internal ip address are getting blocked and time out all of a sudden. My local ip of 192.168.0.150 ...
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0answers
19 views

How much of your web browsing behavior is VISIBLE to the administrators when you're behind HTTPS or VPN? [on hold]

For example. If you're behind a VPN and want to get on on facebook and youtube. Will all outgoing traffic need to make a request to the firewall first? I don't really know extensively how well a ...
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2answers
23 views

How to restrict outbound EC2 to only access S3?

I want to restrict the outbound security group from an EC2 instance. The instance only needs to access an S3 bucket. I just learned that S3 uses port HTTPS (443). I could just put that rule in place ...
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0answers
21 views

Network configuration for Virtual machine based firewall

I have this physical configuration: And I'm planning to install IPFire (or similar firewall : pfSense or Sophos UTM) on a virtual machine on the Active Directory Server to control traffic between ...
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0answers
26 views

How to Draw a Network Diagram of My Office Network [on hold]

Can you please help me out How to Draw a Network Diagram of My work network. We are using all Windows server and using Windows 8.1 Platform at workstaions too. Please help me. Thanks, PK
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1answer
5k views

Handshake violation when trying to access one website

I have a TZ 190 Wireless Enhanced with SonicOS Enhanced 4.2.1.0-20e. Yesterday, people could access without any problems a bank website wich uses HTTPS. Today, it is imposible to access only that ...
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0answers
12 views

How do I use CSF to redirect domain requests to a port?

I have a server setup that uses two different webservers with different subdomains. Right now the servers listen on different ports (80 & 4000) So users don't have to put in :4000 I'd like to ...
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0answers
24 views

Windows Advanced Firewall - Advanced Rules? [duplicate]

my game server is being DDoS attacked (Windows Server 2012). Probably you would say there is nothing I can do but I don't think so because I can use my dedicated server in a normal way, it's just that ...
0
votes
1answer
2k views

Iptable l7-filter installation guide and block p2p

I would install l7-filter to block P2P torrent, First of all , I have a linux debian. I installed by the below command apt-get install l7-filter-userspace And then run command iptables -I FORWARD ...
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2answers
1k views

Smoothwall Express interface issues

I have a SmoothWall Express box that is currently configured with a Green and Purple interface. Both interfaces are in the same /24 subnet (which seems odd to me). The green interface (address of ...
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votes
1answer
53 views

How to open Port 443 on External Firewall? [closed]

I've been trying to configure SSL on my server for last 4 days now, with absolutely no success. I've generated a CSR file and uploaded the certificate and configured a Vhost, but nothing seems to ...
0
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2answers
12k views

Fortigate 200A firewall CPU high resource usage

This morning I'm receiving complaints from several end users that saying their whole department network are slow and have intermittent. Therefore I've checked our firewall to see whether if something ...
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2answers
22 views

Does Windows Network Load Balancing require any specific ports to be open?

I have two Windows 2012 servers, joined in a Windows Network Load Balancing cluster. I have been trying to find how the NLB heartbeat message is exchanged between those servers (to make sure it will ...
1
vote
1answer
20 views

Apache problems in performance test with mod_reqtimeout

We have 2 Apache webserver behind a load balancer wich are connected to 2 (JBoss) application servers via mod ajp. To those webservers, mobile devices connect via a REST API. In our performance ...
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1answer
21 views

Loading fail2ban rules to iptables using iptables-persistent

I am using iptables-persistent package to reload my iptables on boot. And I have been thinking should I add the fail2ban rules to the loaded config file? Now I am seeing they are duplicated. This is ...
1
vote
1answer
1k views

QoS settings for Wi-Fi calling on pfSense firewall/gateway?

The new version of iOS 8 as well as Android supports Wi-Fi Calling with multiple cellular providers including T-Mobile in the US. I am currently running pfSense as the primary Internet gateway for ...
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2answers
54 views

How to enable CentOS 7 to connect to an external SMTP? [closed]

I have a web application deployed in a webserver, running on a CentOS 7. This web application sends e-mails through an external SMTP (in-v3.mailjet.com, port 587). How can I enable CentOS to connect ...
1
vote
1answer
862 views

Should I create a second WAN Interface for a new SSLVPN setup on my Sonicwall 2400?

Sonic Wall 2400 I'm setting up a new SSLVPN on our Sonicwall, very new to this. I currently have an exchange server as well, so mail.company.com is directed to our mail server. I'd like to setup a ...
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votes
1answer
967 views

iptables denies internal access to port 17500

In the kernel log there are hundreds of these lines. The source is the external IP of the VPS (not localhost nor 127.0.0.1), other times an IP of the network of the VPS provider. The source port and ...
17
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1answer
14k views

What does “!Z” and “!X” mean in a traceroute?

When you see "!Z" or "!X" in a traceroute, what does that mean? Where is it coming from, and how do I fix it?
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1answer
27 views

Open source firewall as a virtual appliance? [closed]

Is it possible to have an open source firewall which can run as a virtual appliance into a guest VM where all traffic from the other VMs should go through this firewall VM? And it supports also ...
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votes
1answer
32 views

Block everything except some ports and specific IP Addresses, server can't do HTTP GET

I can't get this firewall.sh script to work. It currently doesn't allow me to get a file at 'https://index.docker.io/v1/repositories/library/ubuntu/images' so either my DNS is flawed or I am blocking ...
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votes
2answers
454 views

Nginx, ModSecurity, IP Tables blocking WordPress dos/ddos attack

For the past 14 days I have had my website being hit by millions of WordPress installs over the world which .htaccess is kind of coping with but I am trying to get something to kick them before ...
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3answers
1k views

Configuring Iptables On CentOS 6 Locks Me Out

I'm running the following bash script as root to configure iptables (I'm logged in via SSH): #!/bin/bash # Delete all existing rules iptables --flush # Set default chain policies iptables -P INPUT ...
1
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0answers
16 views

Hadoop namenode port getting blocked

I have installed 7 VM instances of Ubuntu 14.04 LTS servers. First instance runs the namenode service and all other 6 nodes run datanode service.I think my NameNode is getting crashed or blocked due ...
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votes
2answers
33 views

Is there a way to block ALL inbound/outbound traffic going outside of a LAN with iptables?

As the title says, I'm just looking for a way to disallow any traffic on ANY port unless it's going to a local IP address (192.168.1.*).
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1answer
40 views

How can I adapt this technique of using a proxy (in firefox) to wget and yum ? [closed]

I work in a large organization where some people have extremely restricted internet access and some are given a fairly large amount of freedom. The way my organization manages this is by running a ...
19
votes
7answers
100k views

What firewall ports do I need to open when using FTPS?

I need to access an ftps server (vsftpd) on a vendor's site. The vendor has a firewall in front of the ftps server and I have a firewall in front of my ftps client. I understand that ports 990, 991 ...
40
votes
15answers
16k views

iptables Tips & Tricks

I'm sure Linux sysadmins are quite familiar with iptables, the userland interface to the netfilter packet-filtering framework. Now, this "Question" is meant to be a Community Wiki for collecting ...
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1answer
50 views

How to allow google-analytics via iptables when internet is blocked for other traffic [duplicate]

I am running the following script on a wifi gateway. The WAN side of the gateway has ppp0 interface while LAN side is on wlan0. No LAN user should be allowed to browser internet Some services on ...
8
votes
3answers
36k views

CentOS 7 Firewall Configuration

In CentOS 6 I could type setup from the command line and I would be presented with a set of tools, one of them being Firewall configuration. I can still do this in CentOS 7, except the list no longer ...
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3answers
3k views

Configure multiple lan interfaces for same subnet on sonicwall

We have a sonicwall 2400, Is there any way to assign multiple interfaces to the same lan subnet? Basically, we would like to have X1 for the wan and X0, X2, X3 and X4 connected to 4 devices that would ...
0
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0answers
14 views

pfSense WAN load balancing across two IPs (has single gateway)

My virtual setup has two IPs, but they rely on the same gateway. I had this configured: interface - type - IP address - Gateway em0 - WAN1 - 172.16.155.131 - 172.16.155.2 em1 - LAN ...
0
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1answer
91 views

MikroTik - can't access webfig from external / can't SSH into router from external ip

Ok, here's the deal. Let's say that my public facing IP is 10.0.01. I can't webfig into 10.0.01 from external and can't SSH into mikrotik router from external IP. I can do it if I am physically ...
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votes
1answer
19 views

SSH port blocked EC2

I had installed Tomcat on my EC2 instance . However i was unable to access it using my public IP:8080 . So I followed the instructions mentioned in the post ...
0
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0answers
28 views

Ip6tables firewall make server unreachable on reboot

I am trying to set up a very basic firewall on my server with iptables and ip6tables. My rules get loaded on restart with systemD. The OS is ArchLinux. When I just setup iptables everything works. ...
1
vote
1answer
48 views

Need recommendations on Firewalled DMZ design for PHP web server on Linux

The 3 options we are considering are listed below. Which one is best or is there a better solution we didn't consider. All servers are linux with nginx. Do you see anything particularly wrong with ...
0
votes
2answers
974 views

Routing between multiple Mikrotik Firewalls

I have 2 Miktorik RouterBoards, an RB1100 and a RB951G. The 951G is acting as my Wireless box, and has Guest, Internal and Internet Only Wireless networks. The RB1100 has 3 WAN connections (2x150/10Mb ...
1
vote
3answers
2k views

Sonicwall NSA2400 - No internet access

We've got a SonicWall NSA2400 configured with a LAN (X0) and a WAN(X1) interface. It was setup and working fine until just recently when a temporary worker changed some settings most likely NAT. We ...
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votes
1answer
49 views

remote firewall configuration on centos7

I'm using Centos 7 and am trying to configure my firewall remotely. When I run firewall-config & a window comes up but remains blank. I cannot kill the window with the X close button so I need to ...
0
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2answers
81 views

2 lans on the same switch safe? [closed]

I have a modem with 5 ports. Each port gets a static IP address from the web. Basically if i ping one of those static IP addresses from home i am pinging directly one of those ports. On the first ...
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2answers
1k views

KVM: All network traffic to one guest (firewall)

I am currently using a VMWare ESXi 5.5 server for my virtualisation. The network setup is like this: PFSense firewall is the center of it all and connected to: LAN Network (physical NIC 1 assigned by ...
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3answers
1k views

Automatically block IP who requests certain URL

One of our client's PHPBB (surprise, surprise) got hacked. I have taken it down by simply changing the directory name for now however the address example.com/forum/* is still getting hits from ...
3
votes
1answer
6k views

PPTP connection fails with errors 800/806

I've got a client (Server 2008 R2) that won't connect to our production environment PPTP VPN server (Server 2003, running RRAS). The server is behind a firewall that has TCP1723 open as well as GRE. ...