From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 22 Apr 2008 18:04:18 -0600 From: Jan Hetges Subject: Re: [B.A.T.M.A.N.] two-radio nodes and alternative next hop Message-ID: <20080423000418.GA7368@apoderado.ometepe.net> References: <20080421123928.GA3483@apoderado.ometepe.net> <560c7c9a0804210557v2c94a553w5a2c8dd2efb8eead@mail.gmail.com> <20080421203002.GA4490@apoderado.ometepe.net> <200804221601.57318.axel@open-mesh.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ikeVEW9yuYc//A+q" Content-Disposition: inline In-Reply-To: <200804221601.57318.axel@open-mesh.net> Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: The list for a Better Approach To Mobile Ad-hoc Networking --ikeVEW9yuYc//A+q Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Apr 22, 2008 at 04:01:57PM +0200, Axel Neumann wrote: > Hi Jan, >=20 > On Montag 21 April 2008, Jan Hetges wrote: > > On Mon, Apr 21, 2008 at 02:57:44PM +0200, Benjamin Henrion wrote: > > > On Mon, Apr 21, 2008 at 2:39 PM, Jan Hetges wrote: > > > > what i recognized lately, on two nodes (the ones with more than > > > > one bmx interface), show alternativeNextHops, which are *NO* > > > > alternative. It seems there gets some 'information' lost between > > > > the two IFs. I suppose that's a known issue ;-),=20 > It is NOT a known issue (at least not to me) and if its a bug it should b= e fixed. so, let's fix it then ;-) > > > Can you describe a little more extensively your network configuration? > > x.x.0.0/24---x.x.0.1/x.x.3.1---x.x.3.0/24---x.x.3.160/x.x.4.1---x.x.4.0= /24 > One general questions: do all your interfaces operate on the same frequen= cy? no > Then, I am unsure about the netmasks you are using. The above line I=20 > understand that you are using x.x.3.0/24 and x.x.4.0/24 netmasks.=20 sorry, the /24 only specifys the netrange for the ssid it belongs to=20 > Generally, It is strongly recommended to always use the same netmask=20 > on ALL batman interfaces ! i know, you helped me fixing that :-) and if you look again into my previous mail, i also wrote: batman network x.x.0.0/20. so, ALL batman broadcasting to x.x.15.255,=20 > But according to the debug output there is a direct link to x.x.4.165/24= =20 > (which I guess has broadcast address of x.x.4.255) and therefore the two= =20 > interfaces should not see each other!!?? there are direct links always only in the according /24 netrange, because they are on different channels/ssids, so .3.160 and .4.1 cannot "see" each other.=20 Note, NO .4.x node cannot see ANY .3.x node, even if they would be on the same channel/ssid! >Can you verify that (note that the=20 > "ifconfig dev ip/netmask" command is buggy and does not always produce=20 > corresponding netmask and broadcast addresses and that the interfaces MUS= T be=20 > configured appropriately before the daemon is started. !!!) i recognized the buggy ifconfig and ALWAYS set netmask and broadcast addresses. >=20 > > .0.1/.3.1 is one node with two radios, and .3.160/.4.1 the other one. > > and, .3.160/.4.1 lists .4.162 as alternativeNextHop to .3.128. > > where .3.1 and .3.137 can see .3.128, but .4.162 can not.=20 >=20 > An alternativeNextHop to a specific node must not necessarily be a direct= neighbor of=20 > that node. For example in the following scenario: claro >=20 > A---B---D > | | > +---E---+ >=20 > >From As' point of view B and E may both be potential next hops towards D= =2E But only E=20 > can directly see D. >=20 > Is it possible to generate (almost simultaneously) -cbd8 logs from the in= volved=20 > nodes, especially 3.1, 3.160, 4.162, 3.128.=20 attached, note that .3.137 is down due to power issues, and the link between .3.140 and .3.160 is not usable, but you should see the issue. >=20 > > So, there is a=20 > > real alternativeNextHop to .3.128 ... .3.137, which is listed after .4.= 162 > > on .3.160/.4.1. I attach the output of bmxd -cbd8. >=20 > The attached debug log shows: > 172.19.3.128 wlan0:bmx 172.19.3.1 80 ( 97 1:01:20:33 15813 = 0 100 1012 =20 > 18 2 1 ) 172.19.4.162 67 172.19.3.140 2=20 right, but it SHOULD show .3.137, and NOT .4.162 at all. The ONLY link between .4.x and .3.x IS .4.1/.3.160 (that's the reason for having a repeater there :) >=20 > At least this line does not show 3.137 listed after .4.162 on .3.160/.4.1 > Has it been truncated ?? i don't think so, i'll make some more logs when .3.137 is back up >=20 > Looking forward to solve this... cheers --Jan --ikeVEW9yuYc//A+q Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFIDn0ClTtvZdk47D4RAorIAKCmxwRi5owC6ORUoStX1baxwFDW/ACeJCK9 +yoq5dg0CWlQOqyHaD7Hl3s= =uwIk -----END PGP SIGNATURE----- --ikeVEW9yuYc//A+q--