Hello Sumin, Think of the tables as a way to organize tasks that are somewhat similar. Thus for all the tasks that are related to network address translation, you have the NAT table whereas basic packet mangling (which includes identifying and applying certain 'marks' or something similar) the packet is done in the mangle table. This info can later be checked in the filter table where the actual filtering takes place. Each table thus consists of various chains some of which are there by default whereas one can define custom chains within these existing chains. Thus a table has multiple chains and each chain then contains various matches(optional) followed by a TARGET which gives the verdict. I hope it helps. To see the organizational structure, im afraid u'd have to see the code for the tables which are again implemented as modules (iptable_filter.c, iptable_nat.c etc) in context of the base ip_tables.c . Regards, Aijaz Baig. On 10/19/10, Sumin Xia <xiasumin1984@xxxxxxxxx> wrote: > Hi Aijaz, > > I know that "matches" is used to decide whether a frame matches > certain conditions or not and "target" is used to do a certain action > when all matches of a rule are passed. However, I'm not clear what is > function of "tables". Could you introduce the function of "tables", > please? > > Thanks, > > Sumin > On Oct 18, 2010, at 12:28 AM, AIJAZ BAIG wrote: > >> Hi, >> >> have you read the man page of the ebtables? There are quite a few >> targets which modify the MAC address of a given frame like snat, >> redirect etc. Also please do read the examples at >> http://ebtables.sourceforge.net/examples/basic.html >> and http://ebtables.sourceforge.net/examples/real.html to give you >> a better idea. >> >> Hope it helps. >> >> Regards, >> Aijaz Baig >> >> On Mon, Oct 18, 2010 at 6:56 AM, Sumin Xia <xiasumin1984@xxxxxxxxx> >> wrote: >> Hello, >> >> I am new to ebtables. Recently, I am working on a project, which >> needs to modify mac address of each frame in a middle box in order >> to forward the frame to next expected middle box. I want to know >> whether I can modify mac headers by ebtables. And how to modify it? >> >> Best, >> >> Sumin Xia >> -- >> To unsubscribe from this list: send the line "unsubscribe netfilter- >> devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > -- Best Regards, Aijaz Baig -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
