Difference between Forwarding and routing

Thread Tools Search this Thread
Special Forums IP Networking Difference between Forwarding and routing
# 1  
Old 08-11-2009
Difference between Forwarding and routing

Hello everybody!,
I have a doubt about this, because when i set up a machine to forward packets with IP_FORWARD module, it just decreases the TTL, and forwards the packet to the target.

But when i use iptables filters and NAT, i have to disable ICMP Redirects, because other routers consider it a "router", and they send redirects to client hosts in the network.

In neither cases the host uses routing protocols or something like that, so, what's the difference between them? What does iptables or NAT do to make the other routers consider the host a "router" and what IP_FORWARD module does not?
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

awk to calculate difference of split and sum the difference

In the awk I am trying to subtract the difference $3-$2 of each matching $4 before the first _ (underscore) and print that value in $13. I think the awk will do that, but added comments. What I am not sure off is how to add a line or lines that will add sum each matching $13 value and put it in... (2 Replies)
Discussion started by: cmccabe
2 Replies

2. UNIX for Advanced & Expert Users

Help on port forwarding please..

Hi experts, We have windows machine ( A ) in one network & 2 Linux Servers ( B & C ) in another network. There is a firewall between these 2 networks and SSH (TCP/22) & HTTPS (TCP/443) are allowed from A to B only (but not to C). There is no personal firewall / iptables running on any machine.... (1 Reply)
Discussion started by: magnus29
1 Replies

3. Programming

what is the main difference between difference between using nonatomic lseek and O_APPEND

I think both write at the end of the file ...... but is there a sharp difference between those 2 instruction ..... thank you this is my 3rd question today forgive me :D (1 Reply)
Discussion started by: fwrlfo
1 Replies

4. AIX

X Forwarding broke

X Forwarding has quit working on only 2 of our AIX Servers. ssh -X -vvv host That shows it requesting the X11 forward auth spoofing. No errors. echo $DISPLAY shows the display variable However when I execute xclock.... nothing... Kinda like it just hangs and for some reasons it does... (1 Reply)
Discussion started by: Gibby13
1 Replies

5. Linux

IP Traffic forwarding

Hello All I have the following setup of a network. Client machines sends requests to the server which is ( running on Ubuntu server 8.04. And this server forwards all incoming traffic from clients to another server ( when it's available. The availability is checked... (0 Replies)
Discussion started by: Anuradhai4i
0 Replies

6. Cybersecurity

ssh X-forwarding and remote forwarding behind proxy

Hi, from my workplace we use a proxy to connect to the outside world, including external ssh servers. The problem is that the server is seeing the connection coming from the proxy and knows nothing about the client behind it. The ssh connection itself works fine, but x-forwarding does not work as... (1 Reply)
Discussion started by: vampirodolce
1 Replies

7. UNIX for Dummies Questions & Answers

Email forwarding ? Help !

Hi, I'd like to forward my Emails from my domain to my gmx and web.de accounts. For example: bla@blabla.de to bla@gmx.de blabla@blabla.de to bla@web.de How to do this ? I know that .forward forwards all emails to one account, but that's not what I want. (8 Replies)
Discussion started by: sai
8 Replies

8. IP Networking

ip forwarding

Can anyone out there explain to me how to multi home a nic? I hate to say it but I'm a windows guy forced to learn Unix. The issue I currently have is I can't changed the ip on eth0, but in order to make it pingable by other servers I need to multi home the nic with a totally seperate Ip. Any help... (1 Reply)
Discussion started by: win2khater
1 Replies

9. Shell Programming and Scripting

virus forwarding ?

Hello, I have created a .forward file to automatically forward all e-mails from my unix account to a webmaster account. I want to know if an e-mail that is carrying a virus could infect my server or the server with the webmaster account, or both servers ? (2 Replies)
Discussion started by: silver40
2 Replies

10. IP Networking

IP Forwarding - Newbie Qu

I'm looking to enable IP forwarding from a private LAN thru a Solaris Unix box onto a general LAN. Can Anyone tell me how to go about it ? An example of hte command line would be a great help. Thanx (5 Replies)
Discussion started by: ianf
5 Replies
Login or Register to Ask a Question
Route classifier in tc(8)					       Linux						 Route classifier in tc(8)

route - route traffic control filter SYNOPSIS
tc filter ... route [ from REALM | fromif TAG ] [ to REALM ] [ classid CLASSID ] [ action ACTION_SPEC ] DESCRIPTION
Match packets based on routing table entries. This filter centers around the possibility to assign a realm to routing table entries. For any packet to be classified by this filter, a routing table lookup is performed and the returned realm is used to decide on whether the packet is a match or not. OPTIONS
action ACTION_SPEC Apply an action from the generic actions framework on matching packets. classid CLASSID Push matching packets into the class identified by CLASSID. from REALM fromif TAG Perform source route lookups. TAG is the name of an interface which must be present on the system at the time of tc invocation. to REALM Match if normal (i.e., destination) routing returns the given REALM. EXAMPLES
Consider the subnet being attached to eth0: ip route add dev eth0 realm 2 The following route filter will then match packets from that subnet: tc filter add ... route from 2 classid 1:2 and pass packets on to class 1:2. NOTES
Due to implementation details, realm values must be in a range from 0 to 255, inclusive. Alternatively, a verbose name defined in /etc/iproute2/rt_realms may be given instead. SEE ALSO
tc(8), ip-route(8) iproute2 21 Oct 2015 Route classifier in tc(8)