UFW on Ubuntu to Allow All Traffic on LAN

Question

I want to allow all LAN traffic to my Ubuntu server. I have read the documentation and see the command, but when I try to edit the command for my IP range I get an error. How can I allow all traffic starting at 192.168.15.0 - 192.168.15.255?

sudo ufw allow from 192.168.15.0/255 ERROR: Bad source address

It seems like the 15 (third octal) is causing the error. Almost like UFW does not expect a LAN to have a unique IP set.

Thank you

good question, but ufw is a simple interface above the iptables, you may able to do more control over packets via iptables. i prefer you to read this nice article about iptables: http://www.faqs.org/docs/iptables/ — pylover, Jan 07 '13 at 23:50
@pylover This is not helpful for this question. UFW is useful to simplifiy iptable tasks and what he wants to do is possible with it. — Christopher Perrin, Aug 05 '14 at 18:43

score 49 · Accepted Answer · answered Oct 13 '09 at 13:38

49

sudo ufw allow from 192.168.15.0/24

answered Oct 13 '09 at 13:38

Roy

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Does 0/24 include IPs such as 192.168.15.220? – Christopher Altman Oct 13 '09 at 16:16
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Yes. 192.168.15.0/24 includes adresses from 192.168.15.1 to 192.168.15.254. – Roy Oct 13 '09 at 16:41
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What if i want to allow both (IN and OUT)? ufw allow out from 192.168.15.0/24 to 192.168.15.0/24 ? – 16851556 Mar 07 '18 at 12:22
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For those wondering about the `/24`, see [here](https://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing#CIDR_notation). Essentially, the first 24 bits of the IP address (`192.168.15`) are fixed. – Mateen Ulhaq Jun 10 '19 at 09:55
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I might be nitpicky, but 192.168.15.0/24 is actually from 192.168.15.0 to 192.168.15.255, totaling 256 IPs as 2^(32-24) – fa wildchild Nov 25 '20 at 15:41
You are correct, of course, @fawildchild. I oversimplified for the benefit of the OP. – Roy Feb 02 '21 at 23:55
What about multicast? – yurtesen Apr 27 '21 at 13:55

score 6 · Answer 2 · edited Sep 03 '21 at 12:52

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you need to do sudo ufw allow from yourip/24 like this

sudo ufw allow from 192.168.1.0/24

replace 1 with your ip router.

To allow connections for particular IP addresses ranging from 192.168.1.1 to 192.168.1.254 to port 22 (SSH), run the following command

sudo ufw allow from 192.168.1.0/24 to any port 22

edited Sep 03 '21 at 12:52

Michael Hampton

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answered Sep 03 '21 at 02:57

oceancambo

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This saved the day for me – Merc Apr 07 '22 at 00:20

UFW on Ubuntu to Allow All Traffic on LAN

2 Answers2