Re: [mpls-linux-general] Debian GNU/Linux MPLS installation problem

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On Mon, Jul 18, 2005 at 10:17:51AM +0300, Razvan Deaconescu wrote:
> i tried those packages when i saw it hadn't work (forgot to mention
> that); i  also checked most of the discution list, but nothing helped;
> the same problems arise :-(
>=20
> however, the fact that the kernel versions from 2.6.10 on cannot be
> patched has nothing to do with Debian (what is involved here is the
> mpls support, the linux kernel source code from http://www.kernel.org
> and the patch application)

Check out the pending patches at http://sf.net/projects/mpls-linux/  I beli=
eve
there is one for 2.6.10 there.

> i think i will try working with an earlier version of mpls-linux to
> see if that works;

I wouldn't recommend that.  There is a reason a newer versions are released,
mostly bux fixes.

> could you please tell me if it is normal for the two headers mpls.h
> and gen_spec.h
> not to exist in the /usr/include/linux header folder and to be copied man=
ually

Yes, because your not using a kernel-headers deb that has been modified
for MPLS-linux.

> thanks,
> Razvan
>=20
>=20
>=20
> On 7/17/05, James R. Leu <jl...@mi...> wrote:
> > Please see my recent post about debian packages.
> >=20
> > On Sun, Jul 17, 2005 at 04:43:32PM +0300, Razvan Deaconescu wrote:
> > >        Hi everybody,
> > >
> > > we are trying to install MPLS support on some Linux machines and to g=
et as
> > > many things working as we can; we began with configuring the kernel a=
n testing
> > > the mpls utility using the iproute2 application suite; we chose the D=
ebian
> > > GNU/Linux distribution because we are quite accustomed to it and we c=
an proceed
> > > much faster with this project.
> > >
> > > However we ran into many problems some of which we were able to solve.
> > > I will make quite a detailed presentation of the things we did so far=
 because
> > > we don't want to miss anything important, in case anyone can help us.
> > >
> > > First of all, if anyone has managed to install a functional MPLS supp=
ort on a
> > > Debian GNU/Linux distribution we kindly ask him/her to tell us the st=
eps that
> > > he/she followed and where we went wrong.
> > >
> > > Ok, here it goes.
> > >
> > > We used Debian GNU/Linux 3.1 Sarge as our base system. We used the ne=
twork
> > > install minimal CD available at
> > > http://cdimage.debian.org/debian-cd/3.1_r0a/i386/iso-cd/debian-31r0a-=
i386-netinst.iso
> > >
> > > After the installation, the first thing we had to do was compiling th=
e kernel
> > > with MPLS support. We used the latest available patch mpls-linux-1.94=
6a.
> > > We used (as a test) 4 different kernel versions, namely 2.6.9, 2.6.10,
> > > 2.6.11.12 and 2.6.12.2.
> > >
> > > This is where we ran into some of our problems: only the 2.6.9 versio=
n of the
> > > kernel could be successfully patched; these are the links where you c=
an find
> > > output for the patch applied to the 2.6.9, 2.6.10, 2.6.11.12 and 2.6.=
12.2 kernel
> > > versions.
> > >
> > > 2.6.9:          http://atlantis.cs.pub.ro/~razvand/output-2.6.9
> > > 2.6.10:         http://atlantis.cs.pub.ro/~razvand/output-2.6.10
> > > 2.6.11.12:      http://atlantis.cs.pub.ro/~razvand/output-2.6.11.12
> > > 2.6.12.2:       http://atlantis.cs.pub.ro/~razvand/output-2.6.12.2
> > >
> > >        Because we didn't want to loose to much time, we chose the 2.6=
.9
> > > kernel version. We did a
> > >        # make menuconfig
> > > and added all the options presented in the QUICK.START help file.
> > >
> > >        Afterwards, we compiled the kernel the Debian way (via make-dp=
kg)
> > > and created a debian package containing the compiled kernel image. We=
 installed
> > > the image, restarted the machine and booted the new kernel. Everythin=
g went
> > > smoothly. The next step was testing our kernel for MPLS support.
> > >        By the way, we also tried compiling the 2.6.11.12 kernel (even=
 though
> > > the patching failed). But, as we anticipated, the mpls files attached=
 in the
> > > net/mpls directory were not compiled within the kernel (due to the fa=
ct that
> > > the Makefile in the net/ directory itself couldn't be patched).
> > >
> > >        Back to our 2.6.9 kernel, we browsed to the net/mpls/ directory
> > > and found that the mpls files were indeed compiled and thus inserted =
in the
> > > new kernel. We were left with testing mpls support inside this new ke=
rnel.
> > > As the mplsadm utility is now obsolete, we decided to try the iproute=
2 with
> > > MPLS patching (in order to use the mpls command).
> > >
> > >        We used the RPM source package available at
> > >        http://sourceforge.net/projects/mpls-linux
> > >
> > >        Because Debian also has RPM support we could install the iprou=
te2
> > > rpm source package; this contained iproute2-2.6.9 and also various pa=
tches.
> > > We patched iproute2 (everything went fine).
> > >
> > >        But when we tried to compile it, a lot of compilation errors e=
merged.
> > > All of them were: "_SOME_KIND_OF_VARIABLE_OR_MACRO_ undeclared". We
> > > soon found that the header files mpls.h and gen_spec.h were not prese=
nt
> > > in /usr/include/linux.
> > >        I don't know why this happened (or maybe this usually happens)=
. So
> > > we copied both files from /usr/src/linux/include/linux to /usr/includ=
e/linux.
> > > We also had to install the db library as our system lacked it.
> > > A simple command:
> > >        # apt-get install lidb4.2-dev
> > > solved that problem.
> > >
> > >        After that we managed to compile and install all the iproute2 =
utilities,
> > > including mpls.
> > >
> > >        What we had to do now was test the mpls utility. We used the e=
xample
> > > of James Leu located at http://mpls-linux.sourceforge.net/simple.php.=
 We have
> > > four computers connected in a network, so there was no problem choosi=
ng two
> > > of them to test mpls.
> > >        The command for uml1 went fine. However the fifth one, namely:
> > >                # mpls nhlfe show
> > > lacked the "push gen 10000 set eth0 ipv4 xxx.xxx.xxx.xxx" part
> > > (obviously we were using the eth0 network interface and a private ip =
address)
> > >        The next command:
> > >                # ip route show
> > >        clearly showed the new route being added (but we were left wit=
h the
> > > missing part from the previous command)
> > >
> > >        We moved to the second machine (this is where our problems inc=
rease).
> > > The third command:
> > >                # mpls ilm add label gen 10000 labelspace 0
> > > give us "Segmentation fault"
> > >        the next time we try to run it it just blocks and does nothing=
. We
> > > were left with debugging these problems.
> > >
> > >        Although, somehow empirical, we used printing in order to get =
a grip
> > > of the code flow. Thus we managed to find out exactly where our probl=
ems take
> > > place.
> > >
> > >        I will show the sequence of function call that finally give us
> > > Segmentation fault, and then the sequence that give us the blocking c=
ommand.
> > >
> > >        We are referring to the iproute2-2.6.9 patched source code.
> > >
> > > segmentation fault:
> > >        mpls/mpls.c
> > >        int main (void) -> do_ilm -> mpls_ilm_modify -> rtnl_talk
> > >        (lib/libnetlink.c) -> status =3D send_msg (rtnl->fd, &msg, 0);
> > >                                this is the line where it cracks :-)
> > >
> > > blocking command:
> > >        mpls/mpls.c
> > >        int main (void) -> ll_init_map (&rth1) (lib/ll_map.c) ->
> > >        -> rtnl_dump_filter (lib/libnetlink.c) ->
> > >        -> status =3D recvmsg (rth->fd, &msg, 0);
> > >                this is the line where it blocks
> > >
> > > we am not sure if the failure of this command has anything to do with=
 the
> > > failure of the command for uml1 (# mpls nhlfe show - which lacks part=
 of the
> > > message)
> > >
> > > to make matter worse, we think the problem may affect the kernel; aft=
er the
> > > segmentation fault message, any attempt to shut down or reboot the ma=
chine
> > > will end up in a block with the following message:
> > >        Deactivating swap ... umount: tmps busy
> > >        - remounted read-only
> > >        done.
> > >        unmounting local filesystems ... umount:
> > >        tmpfs busy - remounted read only
> > >        umount: /: device is busy
> > >        done.
> > >        mount: / is busy
> > >        Rebooting ...
> > >
> > >        right here it hangs (have to restart it manually)
> > >
> > >        Many other thing stop working actually, so the problem may
> > > affect the kernel
> > > a bit more.
> > >
> > >        We are sorry for the long message, but we wanted to show in de=
tail
> > > everything we have done so that it may be easier for others to spot t=
he problem
> > > and help us.
> > >
> > > Thank you very much,
> > > Razvan & Dorin
> > >
> > >
> > > -------------------------------------------------------
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> > > _______________________________________________
> > > mpls-linux-general mailing list
> > > mpl...@li...
> > > https://lists.sourceforge.net/lists/listinfo/mpls-linux-general
> >=20
> > --
> > James R. Leu
> > jl...@mi...
> >=20
> >=20
> >
>=20
>=20
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--=20
James R. Leu
jl...@mi...