Questions tagged [firewall]

Typically software that runs to prevent network traffic from reaching a computer. Also a hardware device that works on a network level rather than running on a single computer.

Filter by
Sorted by
Tagged with
53
votes
3answers
62k views

What is the modern way to do port-forwarding on El Capitan? (forward port 80 to 8080)

The old utility ipfw was discouraged in recent versions of Mac OS X and is now gone from El Capitan. What is the modern way to do port forwarding in El Capitan? I simply want port 80 to forward to ...
10
votes
2answers
25k views

Does iOS have a firewall?

Does iOS support a built-in firewall like macOS does? I don't see anything about it in Settings.
6
votes
3answers
30k views

How can I setup my mac (OS X Yosemite) as an internet gateway

It should be possible, but I searched for a day and cannot get a decent HowTo. There seemed to be a Gateway Setup Assistant, but the Wikipedia link only goes to the server app now. Maybe it is easier ...
19
votes
3answers
66k views

How to restrict “Remote Login” (ssh) access to only certain IP ranges?

Can someone please tell me how to restrict SSH access only to certain IP ranges (e.g. local network) and not the whole Internet? I guess this has to be done via firewall.
18
votes
3answers
45k views

How can I open a port (not application) in the OS X 10.6 firewall?

Let me preface this by saying: I do not want to drop my firewall completely Yes, I really do need particular ports rather than an application. So I see that there is the option to allow particular ...
8
votes
2answers
4k views

Can I block ports and network traffic when using Personal Hotspot?

I would like to block ports and network traffic when using my jailbroken iOS device as a Personal Hotspot. The reason is I don't want my backup program, computer updates, or any high bandwidth usage ...
7
votes
1answer
547 views

Always Asked to Configure Firewall for iTunes

Whenever I open iTunes, I get the standard OS X dialog, Do you want the application "iTunes.app" to accept incoming network connections? Every time I click allow, but I am asked the same thing without ...
98
votes
10answers
88k views

How to get rid of firewall “accept incoming connections” dialog?

I've accepted this so many times that firewall should already remember it. For example, I get it for Eclipse when starting my java programs in debugging mode ... sometimes this dialog is displayed ...
18
votes
2answers
15k views

Reasons to prefer Little Snitch over the built-in firewall

Every now and then I browse through software you must have on your mac type lists and more often than not somebody mentions Little Snitch as a must-have application. Now what I think that many people ...
5
votes
1answer
2k views

How to Use Terminal for “Little Snitch” Functionality without Little Snitch

I'm a Terminal newb, and trying to wrap my head around manual "Little Snitch" functionality without using Little Snitch. From the research I've been doing, I've landed on the fact that I need to ...
8
votes
3answers
6k views

Blocking incoming hostile traffic dynamically with PF and fail2ban on OS X

The bigger picture is that I am trying to dynamically block/unblock IPs using fail2ban 0.8.14. I have been following an old guide for OS 10.5 with doesn’t include PF. I think I’ve configured ...
4
votes
1answer
2k views

How can I restrict Mac sharing services to a specific network/adapter?

I want is to set up a Mac to connect to multiple networks. So far, so good. However, I only want to grant AFP access to users on ONE of the networks, but not the other. How can I accomplish this on (...
3
votes
3answers
2k views

How to limit the bandwidth on a per-application (or per-process) basis in OS X Yosemite?

Whenever I use Homebrew or Apple Store to download a large application, it sucks all my available bandwidth and I am then unable to browse the web. How can limit the bandwidth per-application or per-...
6
votes
3answers
14k views

Little Snitch reports outgoing connections for AirPlayXPCHelper for wrong subnets?

After upgrading to El Capitan, I've started noticing annoying connections from the AirPlayXPCHelper to 192.168.1.0/24 subnet (my home network isn't in 192.168.1.0/24 subnet, it's in 172.16.0.0/12 ...
5
votes
2answers
10k views

Mac OS X Server ignores remote HTTP connections, but accepts local ones

I cannot get Mac OS X Server's web server to accept connections from other machines on the same LAN. This is on OS X 10.8.2, running on a Mac mini which originally shipped with Lion Server. I can ...
4
votes
1answer
587 views

All HTTP requests get ERR_CONNECTION_REFUSED, HTTPS works - How to troubleshoot?

Trying to open a http website on any web browser (event telnet) gives a ‘ERR_CONNECTION_REFUSED’ or ‘connection timed out’. However, the same sites can be opened using https. I tried doing a ...
15
votes
4answers
53k views

How to open a specific port in Firewall OS X 10.9.4

How do I open a specific port in the firewall? I can not use the "allow connections from application" as I want to open the port for Jenkins, that is not on the list...
13
votes
2answers
5k views

Disable Little Snitch in guest account?

It's annoying as hell to let others use your computer on a guest account with Little Snitch installed, all the consecutive popups one after another...it's really ridiculous. Also in the event my ...
27
votes
1answer
125k views

Should I block incoming connections from “netbiosd”?

My (application) firewall settings are configured to block incoming connections from netbiosd. I don't recall setting this myself, and wonder what the consequences are. What are the consequences of ...
5
votes
2answers
4k views

What are the numerous incoming connections I see on public wifi for?

In general I have incoming connections disabled by my security software (Little Snitch). But even when I do this, on public wifi, I see numerous incoming connections for netbios and mDNSResponder ...
22
votes
4answers
30k views

How can I get the exact URLs/requests that a program is trying to connect to?

I currently use Little Snitch to control network traffic on my Macbook Pro, and see what my apps are connecting to. Unfortunately, Little Snitch only shows you the hostname that an app is connecting ...
6
votes
3answers
6k views

Questions about how Internet Sharing works

A simple checkbox and a menu allow you to share your internet connection (no matter which interface you get it on) with any other interface (theoretically). But, the guts of this is a little confusing....
4
votes
1answer
2k views

OS X El Capitan port forwarding to Parallels VM using pfctl

I have Parallels Desktop 11, which does not have support port forwarding to VMs (just the Pro version supports it). So I am trying to use pfctl to forward ports to my Parallels VM. I have followed ...
26
votes
2answers
14k views

Xcode.app gets scanned by socketfilterfw (OS X Firewall) at every launch

Situation: When I launch Xcode, socketfilterfw, OS X's application based firewall, starts using a lot of CPU. After some research I narrowed it down to this: socketfilterfw reads all the files in ...
6
votes
2answers
11k views

Migration Assistant fails on Ethernet Mavericks-to-Mavericks migration

I have the following setup and am attempting the use Migration Assistant over Ethernet: Source machine: Early 2009 24-inch iMac running OS X 10.9 Destination machine: Latest MacBook Pro Retina ...
5
votes
1answer
383 views

Mountain Lion firewall is randomly delaying DNS requests

I recently experienced some delays during DNS host resolution on OS X 10.8. To test it I started a simple script which tries to repeatedly resolve the same hostname 20 times: #!/bin/sh for i in `seq ...
1
vote
1answer
840 views

pfctl config to only allow OpenVPN connection

I found what appears to be a suitable guide here, but pfctl complains of a syntax error and "no IP address found for en3" which is my main interface. I have had other pf rules working successfully to ...
3
votes
1answer
2k views

Port Forwarding on Mac Pro with macOS Sierra

I would like to port forward from my macOS Sierra computer with IP address of 152.1.2.3 to my NAS which is 192.168.2.3. Specifically I would like to access the HTTP web server on my NAS at 192.168.2.3/...
3
votes
4answers
7k views

How do I use ipfw to allow LAN access but deny Internet access?

How can I use ipfw (or another tool, if one is available) to allow unlimited access between computers on my LAN, but not allow access to the Internet? (The IPs on my local LAN are 192.168.0.xxx)
1
vote
1answer
614 views

Murus firewall - redirect an ip to localhost web server

Edited to simplify question: using host file, we can redirect a domain (example.com) to localhost: 127.0.0.1 example.com How can we redirect an ip (for example 35.166.133.11) to localhost (web ...
1
vote
1answer
1k views

Application Firewall is not enabling pfctl

I have a development environment that uses the Pow webserver. When I initially set it up, it automatically reconfigured the firewall to allow me to connect to my_project_name.dev urls. Last time I ...
0
votes
1answer
1k views

Migration Assistant fails on FireWire Mavericks-to-Mavericks migration

I have the following setup and am attempting the use Migration Assistant over FireWire: Source machine: Early 2009 24-inch iMac running OS X 10.9 Destination machine: Latest MacBook Pro Retina ...
6
votes
1answer
3k views

pfctl - howto add an anchor and make it active / load it

So i can add an anchor to the already enabled firewall by doing something like this: $ pfctl -a anchor_name -f /etc/anchor_rules.txt the file "anchor_rules.txt" might contain something like this: ...
4
votes
5answers
1k views

I'm trying to block game “X” from accessing the internet including updating

I'm using OS X El Capitan and I'm trying to prevent a game from accessing the internet including blocking it from checking for updates for the launcher or the game itself. I've gone into Security -> ...
4
votes
1answer
356 views

Murus internet sharing not working

I have Murus 1.4.12 and am following the directions to share my internet connection from en0 (static IP connected to Comcast modem/router) through en3. Both the client and server are macOS High ...
3
votes
1answer
2k views

How do I detect failed remote login attempts and block them?

How do I detect failed remote login attempt on my MacBook Pro and how do I block them? My MacBook Pro is on a network with built-in firewall, if that's relevant.
3
votes
1answer
4k views

How to Connect a router to console, using a mac

I just purchased a non-Apple router (a pfSense SG-1000 device by Netgate). As a contingency plan in the event I would forget my web interface password, to then save my bacon, I want to be able to ...
2
votes
1answer
6k views

macOS Sierra 10.12: Configure firewall for a single port (3690)

How can one configure the Firewall on macOS Sierra 10.12 to open up a single port (in this case port 3690)? There's no obvious UI to do this.
1
vote
0answers
246 views

How can I block all ports with PF except port 80 and 443?

How can I block/close (or drop all the packets coming from) all ports with PF except TCP port 80 and TCP 443? So I only want to make use of port 80 and 443 via TCP. I tried this, but I receive an ...
1
vote
0answers
858 views

Airport Extreme firewall logging

I have a newer model (2013) Airport Extreme and have activated remote logging with level 7/debug messages going to a Linux box. However, I find the messages actually getting logged seem minimal, and I ...
1
vote
1answer
274 views

Is the firewall really pfctl, or another instance of pfctl?

I was mucking around with pfctl a while back, didn't get very far and forgot about it. Yesterday, I couldn't ssh into a remote machine. I disabled the firewall in system preferences but still had the ...
1
vote
1answer
236 views

Only HTTPS websites working otherwise I receive ERR_CONNECTION_REFUSED [duplicate]

I am facing annoying problem of only HTTPS websites working on my Mac (in all browsers). I can only visit Google, YouTube, Facebook, Yahoo etc. So far, I tried following: Websites shows error of: ...
1
vote
0answers
69 views

Prevent data on unsecured wireless, until VPN is connected [duplicate]

There's a lot of good advice around about avoiding connecting to unsecured wireless networks, and using a VPN (for all traffic) if you absolutely must use one. What seems to be missing from this ...
1
vote
1answer
850 views

How can I use wifi only for handoff?

Ok OSX wizards... I have a dilemma. In order to use handoff/continuity at work I need to connect my Mac and iPad/iPhone to the same wifi network. Moreover, I also need to be connected to the ...
0
votes
1answer
819 views

How to force open TCP 443 on my machine?

I turned off the firewall. Then, using nmap in the terminal, I issued the statement nmap 127.0.0.1 and got Starting Nmap 7.12 ( https://nmap.org ) at 2016-08-15 11:00 PHT Nmap scan report for ...
0
votes
1answer
92 views

How can I trace the macOS network stack?

In safari, and several other products, I get a network timeout where I have to reload the page, even though I have a full / working Wifi connection. This is a sporadic issue. The problem seems to ...
0
votes
2answers
339 views

Firewall on. I blocked IP 93.184.220.29 with PF but it still popsup in netstat -n

The firewall is on. I blocked IP 93.184.220.29 with PF but it still popsup in netstat -n. How is that possible? jen:~ jen$ sudo pfctl -t blockedips -T show Password: No ALTQ support in kernel ALTQ ...
0
votes
1answer
51 views

Modifing a preference via applescript changes file group

I recently request help about modifying firewall settings via command-line (see my previous question). Everything is working, but I have noticed that whenever I use this command in an applescript, the ...