1
vote
0answers
16 views

Firewall and NAT settings in GSM modem for one server

I have a GSM Modem (PSI-MODEM-GSM/ETH) in field with one device behind, acting as a server. The situation is as follows: "PC" | \_________Dynamic IP: 10.103.153.122 | ...
0
votes
0answers
20 views

Multiple gateways with linux on same subnet using single NIC

I have the following configuration; Firewall 1 (site 1); x.x.x.x/26 subnet on external 10.0.0.0/8 on internal (internal IP 10.0.0.10) Firewall 2 (site 2); x.x.x.y/26 subnet on external 10.0.0.0/8 ...
0
votes
0answers
20 views

Connecting internet uplink to switch or firewall

While I am using Cisco kit, this isn't really Cisco related, more general network design. In the past I have connected internet connections straight in to a layer 3 core switch, 3750X's, 6509's and ...
-4
votes
1answer
47 views

Single machine server with many operating systems [closed]

Could possibly with single one high end Server with supported Virtualization We can have: - DHCP Server (Virtual Machine 1), - Firewall (Virtual Machine 2), - Squid proxy (Virtual Machine 3) - ...
-1
votes
2answers
75 views

Amazon VPC: How to block inbound traffic on specific IP of an instance while allowing on other IPs of the same instance

Specifications I have an amazon VPC instance with the following specifications: Windows 2003 (32 bit). Two Network Interfaces each with 6 IPs. 6 instances of a software (called backweb) installed ...
0
votes
1answer
54 views

IPTables: Firewall with just one Eth device? [closed]

Admittedly I am a novice in the area of firewalls. But I have read on the IPtables and Firewall theory and command options. There is a general diagram by Rusty Russell, the creator of IPtables: ...
-1
votes
1answer
49 views

Back-to-back router configuration [closed]

I have inherited a network where there are 2 routers supposedly configured back-to-back. They are both on the same subnet and only one serves DHCP. There is the possibility that they are not ...
1
vote
2answers
65 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 ...
0
votes
0answers
19 views

VPN User ACL not working

i´m currently testing a Cisco 886VA router for VPN usage. First off here is my client config group: crypto isakmp client configuration group VPN_PRIV key xxxxxx dns 192.168.111.100 pool VPN_POOL acl ...
2
votes
1answer
24 views

Allow only one ipaddress through a cisco firewall without pcs knowing there is a proxy server

We have a PC behind a firewall. (ASA 5505) [PC] => [ASA Firewall] => [Corporate Proxy/Firewall/Anything] => [Internet] :- where the PC and ASA Firewall are under our control... and the rest are ...
0
votes
0answers
22 views

Unable to connect to SQL Server over SSL

I am unable to connect to a SQL Server over SSL. This is the current setup: A server at my location sends data to an external service (SQL Server 2008) using SSL. We are using Websense and an ASA for ...
0
votes
0answers
62 views

The Windows Filtering Platform has blocked a connection - Query User

I'm having a problem with a program trying to access port 135. The Windows filtering platform is blocking the communication. In the windows security logs, the following is displayed: The Windows ...
0
votes
0answers
18 views

Prompt User for decision corresponding Firewall Inbound Traffic NOT APPEARING

Normally when an Incoming Traffic comes, there will be "Prompt the User for a decision corresponding this Inbound Traffic" popup. For some weird reason this popup is not coming out and I'm finding ...
6
votes
3answers
569 views

What's wrong with using windows firewall?

I was developing a system which requires connection between two computers. I decided to connect the two machines together via direct ethernet cable. My boss didn't like it as there is no firewall in ...
0
votes
1answer
49 views

Cant open port on Windows 2012R2

I really never had problem with Windows Firewall, however today on new installation i`m trying to open port 110 but i cant. My firewall rule is: printscreen telnet myip 110 Connecting To ...
0
votes
0answers
36 views

how to whitelist ip, port, protocol and app on a router?

I am looking for the simplest but robust solution to allow user accounts under Windows Server 2012 to use GitHub.com with the GitHub app, but otherwise not a peep is allowed from the server to reach ...
2
votes
1answer
19 views

How to provide access to lan mysql DB from a remote server?

Consider the below network configuration: A client connects with its workstation to the application server on the Web. The application is full HTML, so only browsing through HTTPS is enough to ...
4
votes
1answer
126 views

Why on linux machines, any packets do not pass except icmp, but correctly pass on windows

There is a cluster on proxmox. In a cluster have vm - configured router (pfsense). In the our net have Windows and Linux machines. There is the problem: Windows-machines have access to the internet, ...
0
votes
0answers
21 views

VPN Full Functioning Then Enabled 2nd NIC now VPN not functioning

I had a successful VPN solution stood up on a Dell PE 2650. I configured Ethernet Bridging and all was well. Following the successful configuration and connection of a few clients, I got greedy. I ...
1
vote
3answers
354 views

iptables error: unknown option --dport

The command iptables no longer recognizes one of the most commonly used options when defining rules: --dport. I get this error: [root@dragonweyr /home/calyodelphi]# iptables -A INPUT --dport 7777 -j ...
0
votes
0answers
78 views

Dropping packets with Open Vswitch and OpenFlowControl

I am trying to setup some Flows with ovs-ofctl to block all unwanted incoming packets for a VM. The commands I use are: ovs-ofctl add-flow xenbr0 "priority=65000, table=0, tcp, dl_src=*, nw_src=*, ...
1
vote
0answers
144 views

Sonicwall NSA 2400 Not switching back to Primary VPN after Failover

We are experiencing an issue with our SonicWall NSA 2400 Firewall. We have a secondary gateway over IPSec setup in the event of a failure of our main ISP (which is unfortunately common). The ...
0
votes
1answer
188 views

why does yum update fail in cent os 6.4 when wget and curl succeeds

I am using Cent OS 6.4 in a corporate lab and the yum update fails with the below error: I am able to access the same repositories through browser. [root@LAB1 ~]# yum update Loaded plugins: ...
0
votes
3answers
61 views

How do I stop someone from saturating my line & wasting CPU cycles

My web host shows inbound & outbound traffic with mrtg. I have a steady 3.5mbps inbound traffic from Nigeria. Even assuming the source IPs & destination ports are blocked with Iptables & ...
1
vote
1answer
219 views

How do I allow only certain IPSet set's to access a certain port with iptables?

I'm using IPSet to build IP ranges for different countries as follows : # Canada ipset -F ca.zone ipset -N ca.zone nethash for IP in $(wget -O - http://www.ipdeny.com/ipblocks/data/countries/ca.zone) ...
0
votes
1answer
20 views

How do I specify the external IP when using iptables masquerade?

I'm using this rule to allow internet access through OpenVPN: -A POSTROUTING -s 10.8.0.0/24 -o eth0 -j MASQUERADE However traffic via the VPN is coming from the box's primary IP. eth0 has a /29 ...
7
votes
2answers
325 views

How to configure a small network of computers within a larger university network?

I have a small computer lab (8 HP workstations, 1 HP server, 2 NAS boxes, 1 HP networked printer) where currently all the devices are connected directly to my university's network. Each device has an ...
0
votes
0answers
54 views

Shutting Down Firewall Rules for TMG 2010

Since TMG is being sunsetted next year we have decided to go with a new firewall/web filter and put the TMG 201O server off the network and used ONLY as a front-end authentication/proxy piece for our ...
0
votes
1answer
103 views

Can't obtain ip-addres from my DHCP server

I can't obtain a ip-addres from my dhcp-server and it's going trough a firewall (pfsense), The firewall(pfsense) and DHCP server are two virtual machines on my physical server(ESXI). As rules i use ...
0
votes
2answers
207 views

How to globally limit total number of TCP connections with iptables?

I'm having quite a difficult time figuring out how to REJECT both inbound and outbound connections from a machine with iptables once the total number of TCP connections hits a global maximum without ...
0
votes
0answers
12 views

VPN through Netscreen Firewall

I have 2 netscreen FWs , I'd like to create Dialup VPN to FW2 as endpoint , passing thru FW1 client ------ FW1 ----- FW2 Is that possible ? I allow 'ANY' from client on FW1 to FW2 endpoint But ...
1
vote
2answers
105 views

How to identify and differentiate networks so I can set location?

I am a developer and know just whatever sysadmin/networking/etc stuff I've picked up over a lifetime of computing and developing (not an inconsiderable amount, but I am very far from an expert on any ...
0
votes
1answer
72 views

Iptables log clent IP to file

Im trying to track whether some ports are being used, and what by, as I want to close them. I have made some iptables traffic counters, and have worked out is a small amount of traffic, coming into a ...
0
votes
2answers
424 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 ...
0
votes
1answer
86 views

route cisco sg300 traffic through Watchguard firewall

I need help in determining what I need to research. I have two cisco SG300 switches (sg300-52 & sg300-28) and a Watchguard firewall (XTM-23). The internet connection currently passes through our ...
-2
votes
1answer
82 views

VLAN routing setup with VPN on Cisco ASAs

We currently have two ASA5515-X firewalls, what we want to do is dedicate one of them to providing AnyConnect VPN and two site to site VPNs only, with the second ASA handling firewall ACLs for ...
3
votes
1answer
262 views

Symmetric NAT and UDP Hole Punching

I've read this question, but the explanation of Symmetric NAT wasn't detailed enough. Please could someone help me to understand the following paragraphs? I read this about Symmetric NAT: Each ...
2
votes
1answer
271 views

Difference between TCP ping and Socket Connection

I have written an network discovery code to discover the devices on the network.The code should discover the devices on the network even if the icmp echo response is disabled . I read about tcp ping ...
0
votes
1answer
81 views

Memory usage on my firewall [duplicate]

I have a memory usage problem with my Checkpoint Firewall (it's a physical firewall). On my monitoring software OPManager I can see that 94% of my memory is used. In SSH, when i enter this command : ...
9
votes
3answers
249 views

advantages in closing a port where no services are running

Are there advantages in closing a port where no services are running? What do I gain in terminating a connection at iptables level instead of what does it next (I guess OS).
-1
votes
0answers
121 views

Need iptables commands to permit all WAN originating traffic to enter the LAN side of a router [closed]

I have three routers. Router0's WAN interface connects to the ISP, and the WAN interface of Router1 and Router2 connect to Router0's LAN interfaces (i.e. hard wired). So this is what it looks like, ...
0
votes
1answer
45 views

Extend subnet with dfl-800

i have 2 locations which are connected with vpn over internet with 2 dfl-800 firewalls. Address config in firewall: Location 1 address 192.168.0.0/24. (no dhcp) Location 2 address 192.168.5.0/24. ...
-1
votes
1answer
253 views

I can't access my computer through specific port

On Fedora 18 I tried to access port 1521, so I opened the following port on my firewall: $ sudo iptables -I INPUT -i eth0 -p tcp -m tcp --dport 1521 -j ACCEPT $ sudo service iptables save and $ ...
-1
votes
1answer
79 views

Netgear FVS338 firewall and VPN [closed]

I have a Netgear FVS338 Firewall and would like to be able to VPN into my home network. I noticed Netgeaar has this VPN Lite/Professional. Do I need to use that or can I use something else? I ...
0
votes
1answer
70 views

Get IP of the “requestor” when doing iptables NAT

I am doing NAT traffic forwarding using iptables (1.1.1.1 => 2.2.2.2) with the following commands: iptables -t nat -A PREROUTING -d 1.1.1.1 -j DNAT --to-destination 2.2.2.2 iptables -t nat -A ...
0
votes
1answer
87 views

How can I un-firewall port 80 on AWS Ubuntu Raring?

I have a web server I'm trying to make accessible, and although from the command line I get a connection by typing telnet localhost 80, it refuses nonlocal connections. The server is an AWS EC2 node, ...
3
votes
1answer
862 views

How do I forward/NAT all traffic to one interface/IP to a remote IP?

I have one "server A" that has multiple IPs attached to it, like so: eth0:0 1.1.1.1 eth0:1 1.1.1.2 eth0:2 1.1.1.3 I have another "server B" that also has multiple IPs attached to it, like so: ...
9
votes
3answers
2k views

Exposing multiple servers behind NAT using a single public IP address

This is a Canonical Question about NAT and DNS I'm currently trying to set up a network with a DMZ containing a web server and an e-mail server separated from the Internet by a network address ...
-2
votes
1answer
57 views

Setting up a DHCP/Proxy Server

Current setup: Modem -> Firewall(DHCP) -> Switch and Wireless Router |-> Computers If I wanted to setup a Proxy Server in there, it would have to replace the Firewall correct? The idea is so that ...
0
votes
1answer
47 views

Filtering input with iptables: -i <interface> versus -d <ip>

I'm changing my iptables setup to cope with the addition of a new uplink, which now receives its configuration through DHCP. I currently list my interface's IP addresses directly in my rules, which ...