Contents
- 1 Which of the following best describes the difference between the drop and reject targets in iptables?
- 2 What is the difference between drop and reject in iptables?
- 3 How do I change the order of iptables rules?
- 4 Is it better to set-J reject or-J drop?
- 5 How to reject traffic from a range of IP addresses?
Which of the following best describes the difference between the drop and reject targets in iptables?
The difference between DROP and REJECT, is that with REJECT, a “connection reset” for TCP and a “destination host unreachable” for UDP/ICMP is sent to the packet source, while DROP dictates that nothing is to be sent to the packet source.
What is the difference between drop and reject in iptables?
The difference is that the REJECT target sends a reject response to the source, while the DROP target sends nothing. This can be useful e.g. for the ident service. If you use REJECT then the clients doesn’t need to wait for timeout. The DROP target doesn’t send nothing.
How do I change the order of iptables rules?
There is no such command to swap two iptables rules. You can just delete and insert them into appropriate position.
What’s the difference between reject and drop in iptables?
The manpage of IPtables says it drops the packet on the floor, i.e. it does nothing with the packet. REJECT differs to DROP that it does send a packet back, but the answer is as if a server is located on the IP, but does not have the port in a listening state.
Is there a way to reject a closed port without iptables?
Without iptables rules, a closed port defaults to REJECT. If you DROP every port it’s a fine alternative (your host appears down) but if you DROP only specific ports you’re actually giving them more information than REJECT.
Is it better to set-J reject or-J drop?
This post explains the reasoning in detail: A common reason for using DROP rather than REJECT is to avoid giving away information about which ports are open, however, discarding packets gives away exactly as much information as the rejection.
How to reject traffic from a range of IP addresses?
You can REJECT traffic from a range of IP addresses, but the command is more complex: sudo iptables –A INPUT –m iprange ––src–range 192.168.0.1–192.168.0.255 -j REJECT The iptables options we used in the examples work as follows: –m – Match the specified option.