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

learn more… | top users | synonyms

-1
votes
2answers
33 views

Resolve external DNS entries conditionally by request network source [on hold]

I recently set up Sophos UTM as public firewall/ALG which I use for all kinds of things, such as VPN server, reverse proxy. When I tried configuring the DNS for my external domains, I had to notice ...
3
votes
1answer
22 views

Is the use of the RELATED state in iptables used properly?

I have been seeing many people using the ESTABLISHED and RELATED flags together to ACCEPT traffic through once a connection was previously accepted (see Allowing Established Sessions). Say I setup my ...
1
vote
1answer
14 views

Using two openvpn clients to expose services of a server

I am currently attempting to use two openvpn clients to expose services of a server, as is already said in the title. I may be playing with powers far beyond my current comprehension, but please bear ...
0
votes
1answer
22 views

How to enable firewall on Centos 7?

My firewall is currently inactive. systemctl status firewalld firewalld.service Loaded: masked (/dev/null) Active: inactive (dead) I used the following command to enable the firewall # systemctl ...
0
votes
1answer
23 views

How to setup monitoring of nodes behind firewall

As lame as it may sound: I am trying to configure monitoring for our production system which consists of 2 hardware boxes with ESXi on both and multiple VMs. All of this is hidden behind a firewall ...
0
votes
0answers
16 views

Remote packet capturing using fifo and dumpcap

I'm currently working on two linux servers where one server is running in 2.6.18-274.el5(Server A) and the second one in CentOS 7 (Server B). My requirement is to capture the packets of the network ...
3
votes
1answer
29 views

Nmap external scan shows port open, ASA says port is not open, but do get an socket

Folks, have a weird one, need your expert help. For one of our heavily used external facing server which came up in an audit, nmap -Pn scan shows the following: Starting Nmap 5.51 ... Host ...
0
votes
0answers
11 views

SIP RTSP and grandstream [on hold]

I have a sip device http://www.grandstream.com/products/surveillance/gxv3615/documents/gxv3615_usermanual_english.pdf that I can connect to it's rtsp webserver in vlc and can see the video streaming ...
1
vote
0answers
8 views

Firebox x700 Reset to Default Not Working

I found a site that explains how to reset a Firebox 700 series back to default as you can see from this link: https://www.hashdoc.com/documents/7502/how-to-default-a-watchguard-firebox-700-or-x700 ...
2
votes
0answers
26 views

Solving an asymetric HA Firewall/router

I have an old Linux HA firewall/router setup that never quite worked. As it was never quite put into true production (just testing and demo's), I always had to have one firewall shutdown to make it ...
0
votes
0answers
15 views

iptables, after specifying an interface to drop traffic it drops all traffic of all interfaces

We have currently the situation that one interface (eth0) is linked to the internet. and we 2 other devices (eth1/eth2) for management purposes. Now the idea is to block off eth0 completely from the ...
0
votes
0answers
7 views

Open ports in firewall on Cisco SRP500 Series?

I have a Cisco SRP527W. I cannot work out how to open ports in the firewall for all machines. In the past, I port forwarded to the server, but now I just want a port open to all users of the network. ...
1
vote
2answers
43 views

How do I drop requests from dig?

Basically I'm getting tons of request to my named/bind service, basically those requests are being rejected by named, Those are the messages i get, from tons of ips., How extacly can I drop those ...
0
votes
0answers
9 views

Block ICMP flood from a specific IP with pf [migrated]

I'm getting a lot of ICMP throttle messages in my system.log: Apr 11 20:45:28 kernel[0]: Limiting icmp unreach response from 1054 to 250 packets per second Apr 11 20:45:29 kernel[0]: Limiting icmp ...
1
vote
0answers
20 views

Synology ssh port receiving too many intrusion attacks, how to ban systematically? [migrated]

I have a synology NAS which I leave at home, and leave it open so I can access it remotely from the office. One of the useful things to do is enable the ssh port so I can access it with my terminal. ...
0
votes
0answers
22 views

pfsense routing with dmz wan and sonic wall

Pfsense setup: 2 physical NIC's (1 input from modem/ISP, 1 LAN with a lot of vlans and DMZ) Network setup: WAN block from ISP xxx.xxx.xxx.225/28 Modem -> pfsense -> vlan 40 (192.168.40.0/24) ...
0
votes
1answer
86 views

No response from a remote linux server on specified ports

I have a remote CentOS 6.5 server that is running a tomcat 8 web server (AKA servlet) on port 54321 and I can't access it from my computer, although I'm establishing a successful SSH connection ...
0
votes
2answers
47 views

Ubuntu Iptables Dual Wan - Forward wan 1 & 2 to an internal server

I'm having problems configuring iptables rules on a double wan setup. The OS is Ubuntu 12.04 LTS. I have 2 Wan connections, both with static IP. Wan-1 is on eth2, Wan-2 is on eth4. I want both of ...
2
votes
1answer
24 views

With SonicWall, cannot access URL inside network

We have a website running on port 80 on our network. Port 80 is forwarded outside of the network, and it is accessible through a URL that points to the IP or the IP itself. However, inside the ...
0
votes
0answers
34 views

ubuntu firewall blocking smtp tasks, port 465 is open

I have been trying to get my Wordpress site able to send emails, and it DOES WORK but only work if I turn off the firewall. I am using UFW. However, I do have port 465 (connecting to gmail) open while ...
-1
votes
2answers
39 views

IPTables not blocking IPStresser [closed]

I have been trying four days to block DDoS attacks with no success. I want to block anything that isn't whitelisted. This is my idea on OS Centos 7: //Delete All Existing Rules iptables --flush ...
1
vote
4answers
118 views

Cisco ASA Implicit rule dropping traffic

The network is as follows: Two Default Gateways exist on the network - one which provides connectivity to the an MPLS with several subnets. Let's say 10.0.0.2 Another which is a Cisco Firewall, on ...
-1
votes
1answer
40 views

Multiple Gateways on LAN

This is more a theoretical question. Let's assume we have a Firewall/DG (with a connected WAN) on LAN IP 192.168.1.1. All external DNS records for incoming services like OWA, FTP etc. point to this ...
0
votes
1answer
24 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 ...
0
votes
0answers
11 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 ...
0
votes
2answers
41 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 ...
0
votes
0answers
28 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 ...
0
votes
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
26 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 ...
-4
votes
1answer
61 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 ...
1
vote
2answers
27 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 ...
0
votes
1answer
32 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
43 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 ...
0
votes
2answers
70 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
votes
1answer
36 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 ...
-1
votes
1answer
43 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 ...
1
vote
0answers
28 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 ...
-1
votes
2answers
35 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.*).
-1
votes
1answer
62 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 ...
0
votes
0answers
24 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 ...
-1
votes
1answer
21 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
votes
1answer
239 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 ...
0
votes
0answers
31 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. ...
2
votes
1answer
64 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
0answers
24 views

Allow URL:Port in Forefront TMG

I have Forefront TMG 2010 installed as a Proxy server to limit internet access to users. I usually have the following issues: 1- I can't configure Email clients (Outlook) with URLs of POP/IMAP and ...
1
vote
2answers
30 views

Is it possible to limit which hosts are accessible through SSH tunneling?

I have a box that runs both an ssh server and a webserver. I would like to prevent people with ssh accounts from using this box as an anonymous proxy to the rest of the Internet (e.g. by creating a ...
1
vote
1answer
41 views

Benefits of separate firewall product over AWS Security Groups for spam requests

I have a question that is an extension of this one: Examples where an AWS Security Group is not sufficient as a firewall?. Initially, the answer in that question made sense to me and I was working ...
-1
votes
1answer
29 views

Firewall throughput [closed]

I saw on multiple site vendor sites about firewall throughput in 1518/512/64 bytes UDP packet and each result from 1518/512/64 bytes UDP packet is 1xxx/smaler than 1xxx/significantly smaller than ...
0
votes
1answer
11 views

How to block or forward packets with custom and dynamic rules

I would like to block or forward TCP requests from clients to WAN according to source and destination ip addresses. The problem is that this ip couples are stored in a mysql database and they can ...
-1
votes
1answer
47 views

Find source(s) of dropped packages in Cisco ASA GUI

we are using pair of ASA 5520 Firewalls with ASDM 6.4. Can someone enlighten me, how to find out which is(are) the source or target ip(s) when we got a hugh bunch of dropped packages come in (by ASDM ...