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

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On Cisco firewall, show access-list main rules only (with line numbers)

For example, if I do a sh access-list Lets say I have a rule on line 2 that has one object-group to another object-group connected on X ports. Well, there may be 30 lines below that, that all say ...
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22 views

MySQL on Ubuntu. 10061 error on 3306

A fresh install of Ubuntu inside of a Virtualbox with LAMP option selected. I am unable to connect to the server via telnet on this port or via ODBC from my host machine. I can ping and SSH both ...
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19 views

iptables, ufw, and psad - scanned UDP port alerts from router and devices on home network

I have a fresh install of Ubuntu 16.04. I configured iptables, ufw (with gufw), and psad using instructions from https://www.thefanclub.co.za/how-to/how-secure-ubuntu-1604-lts-server-part-1-basics and ...
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2answers
44 views

iptables - access to port 3306 timeout

I cannot connect to mysql from a remote server. I have bind-address commented out but when I add rules in iptables to block other connections the requesting server's connection times out. I tried ...
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1answer
3k views

Open port 8009/tcp on Fortigate necessary?

A nmap scan of a Fortigate Firewall showed that TCP port 8009 open is. According to knowledge base articles this is only to download the client for ssl vpn. Is this port used for anything else, and if ...
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0answers
24 views

Transferring data to Active FTP server fails from DMZ but works fine from LAN

I know there are a ton of similar questions already, but I've read through just about everything I could find and am still having trouble resolving my specific issue. Problem: I am having difficulty ...
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1answer
1k views

Ubuntu 12.04 open port 80 inside VLAN

I have an nginx server running on ubuntu 12.04 that serves http through port 80 and https through port 443. Everything works fine if I access it from the same computer via localhost, 127.0.0.1 or the ...
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1answer
33 views

Firewall rules for ssh, ftp and webapps

I'm running a small cluster with Centos 7 and want the following rules for firewall. Have ssh access from anywhere (i'm going to further configure that from /etc/ssh/sshd_config) Have ftp access to ...
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1answer
1k views

Amazon EC2 Socket connection not being accepted

I am trying to run a java application on my EC2 instance. The application accepts socket connections on port 54321. If I try and connect to it, it times out. My Security Group is set as: TCP Port ...
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4answers
6k views

Expert iptables help needed?

After a detailed analysis, I collected these details. I am under a UDP Flood which is more of application dependent. I run a Game-Server and an attacker is flooding me with "getstatus" query which ...
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4answers
3k 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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1answer
23 views

Issue in Accessing FACEBOOK site in Domain network

In our Domain,We have setup firewall to prevent unwanted access to the websites. But a weird thing is even network administrators(whose IPs are not blocked by firewall) cannot access to facebook ...
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2answers
3k views

iptables block client ip internet access and keep LAN access

With the increase of appliances having network access and the potential for hacking, I want to block specific ip address from accessing the internet, but allow LAN access. For instance, I use a ...
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0answers
18 views

Does IKEv2 (Windows Client) require the client firewall to perform NAT-T?

I am kind of new to IPSec VPNs. I am trying to set up an IPSec implementation using libreswan with IKEv2 for road warriors. Being road warriors these clients will likely be behind their home ...
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0answers
18 views

Disable load balancing fortigate 100D

I have wan1 with static ip, wan2 ppoe Port 1 with address 192.168.1.0/24 Port 2 with address 10.0.0.0/24 I just want port 1 go through wan1 and port 2 go through wan 2. No load balancing Every time I ...
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2answers
4k 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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0answers
57 views

FTP protocol Extremely slow on Windows 10. What could be causing this?

I am running 2 different devices (A pc and a laptop) both on the same network, both Windows 10. The laptop has standard transfering speeds on the FTP protocol. The PC has extremely slow transfer speed ...
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2answers
47 views

Check if iptables rules are working

I have three virtualboxs. 1) Virtual machine VM-A that works as a router with two interfaces: eth0 - 10.160.10.254 eth1 - 172.10.0.254 2) Virtual machine VM-B that works as an internal network ...
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0answers
23 views

netfilter, block port range [31000-32000] on public interface eth2

I need to block the port range [31000-32000] on my public interface eth2. Services can be accessed using private network interface eth3 I have tried : root@master-sbg-01:~/# iptables -A INPUT -i ...
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2answers
51 views

RPC Server is unavailable while trying to promote a domain controller. Open firewall

So I've been scratching my head around this problem for a few days now. This is a quick schema of our infrastructure : Our Primary Domain Controller is running in an hypervisor, in our datacenter. ...
0
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1answer
33 views

IIS ftp server issue from command line

I'm trying to config an ftp server on IIS (Windows Server 2008 R2) I configured basic authentication with read,write permissions for a user and no SSL I also opened port 21 on server firewall then ...
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0answers
39 views

Block incoming traffic in bonding mode when primary interface is down

My server running on latest kernel (4.4.6) has configured a bond device (bond0) with two enslaved interfaces eth0, wlan0 with primary interface eth0. cat /proc/net/bonding/bond0 Ethernet Channel ...
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1answer
70 views

Azure ARM VM creation with Network Security Groups

I have a network with enabled Network Security Groups where I deny Outbound Port 80 and 443. All Outbound traffic is managed through a Squid Proxy. Now, I want to create a new Virtual Machine in this ...
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0answers
18 views

How to isolate two containers connected to the same bridge?

I have several LXD containers which are bound to a single bridge (the default lxdbr0 or another one, it does not matter). The host itself has another two interfaces, one ultimately connecting it to ...
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3answers
2k views

IP Address Conflict with Router/Firewall

I've been having IP issues with my local box for a couple months now. Usually when it starts acting up I don't have the patience to look into it, so I just drop onto DHCP, but this morning I've ...
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0answers
18 views

Iptables linux routing with 2 chain proxies

Im trying to setup a connection between a PCs in my local network, to foreign resource XYZ in a specific way. My network is currently configured like this: I have a pc behind the proxies -> Then I ...
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0answers
33 views

Not able to RDP to the VM which is part of new subnet in Azure virtual network

Here are my environment detail I am using Azure IaaS (Infrastructure as Service) I am having one vNet (Virtual Network) I have set-up site to site connectivity (on-premise to azure) I have one subnet ...
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2answers
12k views

tcp syn checking

I have a WatchGuard Firebox that I've recently configured. All of the policies look fine and all appropriate services seem to be working correctly. However, one or two (seemingly) random nodes keep ...
0
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1answer
98 views

OpenVPN Ubuntu Server Routing Problems No Internet

I'm running OpenVPN on Ubuntu 15.04. When I connect to the server, I can connect and authenticate correctly (I use PAM auth because I'm lazy). Once connected I can't ping the server or access the ...
0
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0answers
12 views

CSF Firewall unblock countries

I've a VPS Server running CENTOS 6.7 x86_64 with CSF Firewall activated. Sometimes I see in "Firewall Deny IPs" that blocks suddenly connections from my country (Spain) to some of my clients. Not ...
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3answers
37 views

UFW: How to block http requests on another port than 80?

I am running an application on port 7000 which is part of a network. So it has to communicate over port 7000 with all other servers of the network (not LAN, dynamic IPs). It has also a web frontend ...
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1answer
45 views

How can I block access to the internet for static addresses?

I have a router on CentOS 7 which provides access to internet for several IP addresses, which are reserved at DHCP server. Other hosts are blocked. If someone put static address from the reservation ...
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0answers
27 views

Sizing Firewall for Micro-Datacenter

We have a small data center we're finishing. We have a core+spline and then redundant TOR switches. Everything is basically whitebox 10gb switches running Cumulus; although, we will upgrade the core ...
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1answer
105 views

CentOS port forward

I have the following situation: Internet ----- Server ------- virtual machine (kvm) public ip 192.168.122.12 x.x.x.x I need to make service on the port 3333 ...
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0answers
72 views

ssh login timed out after enabling the ufw firewall ubuntu server

I followed digital ocean tutorial to enable the firewall in my ubuntu server. The steps I performed is: 1> change the port no to some other no. (8338) 2> enable firewall using sudo ufw allow ...
4
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4answers
21k views

What host names and ports would need to be opened in a firewall to allow Windows Updates to work?

We have a set of public web servers behind a firewall we would like to be able to perform Windows Updates on, without giving them more access than they need. Besides www.update.microsoft.com:443, ...
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4answers
16k views

Centos iptables open port 53

I am having problem opening port 53 on my centos machine, for DNS configuration. Here is my iptables config -A INPUT -p udp -m udp --sport 53 -j ACCEPT -A OUTPUT -p udp -m udp --dport 53 -j ACCEPT ...
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0answers
64 views

IPset Alternatives and Firewall Management

I have CentOS 7, Plesk 12, 8GB RAM VPS. I have around 1000 rules in my IPtables to block abusive users. But when reloading IPtables it takes 15 seconds to reload all 1000 rules. First of all, is it ...
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0answers
18 views

Self signed Cisco VPN Certificate

So I just rented some servers protected with a Cisco Firewall from a data center provider. I plan on accessing these servers through VPN. The instructions from the data center provider was to ...
6
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5answers
170 views

Adding second firewall to ISP connection with multiple subnets?

My routing knowledge is a little rusty. I have a fibre internet connection hooked up like this: The managed switch breaks out VLANS for transparent lan service that is also through the ISP's box. ...
0
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1answer
1k views

Set adapter to use Windows Firewall Public Profile

I'm configuring a server to provide VPN access to employees on the road. This server is virtualized, which means that both the Internal and the External network adapters, are actually connections to ...
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1answer
39 views

Centos 7 network issue

I have a Centos 7 server behind a Dell sonicwall I have configured the sonicwall to allow certain services and this seems to work fine. However I can't telnet to some ports. I have added Wireshark to ...
0
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1answer
72 views

ASA INSIDE to INSIDE traffic being dropped

An ASA 5505 is being used to route between two networks as it contains routes to everything. The following depicts the network topology. I have tried various combinations of access lists such as: ...
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2answers
76 views

How to open firewall to access azure file storage

We are going to use robocopy to keep a stack of encrypted files synced to an azure file share. But what do we need to open on the firewall to let the backup server get to an azure storage file share? ...
0
votes
1answer
26 views

ZyWall USG 50 locked out

A Friend of mine was testing something in our Server Room. He made a firewall Rule on the Zywalls' web-interface like this: Block All from All to Zywall So, now we cant access the Webpannel anymore ...
3
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0answers
105 views

Hacker bypassing iptables

(moved from SO) I have iptables protecting a sip server. It blocks all IPs except ones I specifically opened, and it seems to work for almost everyone. I have tested from lots of ip addresses that ...
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1answer
1k views

“Could not generate DH key pair on the destination URL” error

What could cause a Could not generate DH key pair on the destination URL error? A EDI partner company tries to connect to our HTTPS server and encounters the above message. Or system uses a ...
2
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1answer
37 views

IPTables Configuration to allow all connections, only close/deny once data is sent

I'm looking to set up my IPTables firewall in such a way that: Any new connect() is accepted Once data is received: If the destination port is on a whitelist, continue allowing the connection and ...
0
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1answer
29 views

Why is lfd prematurely removing blocks?

As you can see in the excerpted log file below (from /var/log/lfd.log), lfd is prematurely removing temporary blocks that it imposes on IPs: Apr 7 13:07:59 host lfd[32117]: (wordpressxmlrpc) Request ...
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2answers
1k views

Running multiple services on one Port 443 is possible?

I am new to network and firewall things, In our 2008 R2 server i have configured WCF service on windows service with port 443 and later i found another windows service already using the same port ...