mpls-linux-general

[mpls-linux-general] Mpls installation problems with the new version.

[Oliver H. <ho...@tm...>]

Hi,

I try to install a mpls network, in a first step with two PCs.
I use kernel 2.4.18 and the mpls version 1.152, July 27, 2002.

PC1: obiwan (192.168.2.1)  <---> PC2: amidala (192.168.2.2)

Each PC has a network card with 4 slots (to build up a bigger network
later).

--- config section start ---

Configuration of PC1:
Label 21 (push and send) and label 22 (receive and push) 

[root@obiwan root]# cat /proc/net/mpls_labelspace 
eth1	0	12
[root@obiwan root]# cat /proc/net/mpls_in         
0x40005400 189/21369/0 gen 21 0 1 POP PEEK 
[root@obiwan root]# cat /proc/net/mpls_out 
0x00000004 666/51158/0 2 PUSH(gen 22) SET(eth1,192.168.2.2) 
[root@obiwan root]# /mnt/image/pkg/ip route add 192.168.2.2/32 via
192.168.2.2 lsp 0x00000004
[root@obiwan root]# netstat -rn            
Kernel IP Routentabelle
Ziel         Router       Genmask      Flags   MSS Fenster irtt Iface
192.168.2.2   192.168.2.2   255.255.255.255 UGH     40 0    0 eth1


Configuration of PC2:
[root@amidala root]# cat /proc/net/mpls_labelspace 
eth0	0	11
[root@amidala root]# cat /proc/net/mpls_in         
0x40005800 738/59582/0 gen 22 0 1 POP PEEK 
[root@amidala root]# cat /proc/net/mpls_out 
0x00000012 238/25613/0 2 PUSH(gen 21) SET(eth0,192.168.2.1) 
[root@amidala root]# /mnt/image/pkg/ip route add 192.168.2.1/32 via
192.168.2.1 lsp 0x00000012
[root@amidala root]# netstat -rn
Kernel IP Routentabelle
Ziel        Router        Genmask        Flags   MSS Fenster irtt Iface
192.168.2.1    192.168.2.1    255.255.255.255 UGH     40 0      0 eth0

--- config section stop ---

Now I tried to see, that I am really using MPLS. For that reason I have
installed ethereal.

Now I have the following problems:

If I ping obiwan I get the following output of tethereal:

2615.091161 02:01:08:00:36:94 -> c0:a8:02:02:c0:a8 0xb909 Ethernet II
2615.091215   obiwan-2-1 -> amidala      ICMP Echo (ping) reply

What the hell is 02:01:08:00:36:94? It looks like a MAC address, but we
have no cards with these address.
The answer of obiwan looks good. I had a look on it with ethereal and it
looks like a "normal" mpls header.
But the ping request is bad. With ethereal I saw, that there are 6
MPLS-Headers are included. But why? I appended the output of ethereal.

The second thing is, that I am able to ping obiwan, but a traceroute to
the same IP (only one hop of course) generates no output. I have to
press cntl-c.
[root@amidala root]# traceroute 192.168.2.1
traceroute to 192.168.2.1 (192.168.2.1), 30 hops max, 38 byte packets

[root@amidala root]#

So whats wrong?
Maybe I have patched the wrong version of iproute2?


I hope someone can help me.
Thanks.

Oliver

Re: [mpls-linux-general] Mpls installation problems with the new version.

[James R. L. <jl...@mi...>]

http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/mpls-linux/mpls-linux/NOTE?rev=1.5.2.2&only_with_tag=mpls-linux_1_152&content-type=text/vnd.viewcvs-markup

On Wed, Jul 31, 2002 at 04:35:47PM +0200, Oliver Horvath wrote:
> Hi,
> 
> I try to install a mpls network, in a first step with two PCs.
> I use kernel 2.4.18 and the mpls version 1.152, July 27, 2002.
> 
> PC1: obiwan (192.168.2.1)  <---> PC2: amidala (192.168.2.2)
> 
> Each PC has a network card with 4 slots (to build up a bigger network
> later).
> 
> --- config section start ---
> 
> Configuration of PC1:
> Label 21 (push and send) and label 22 (receive and push) 
> 
> [root@obiwan root]# cat /proc/net/mpls_labelspace 
> eth1	0	12
> [root@obiwan root]# cat /proc/net/mpls_in         
> 0x40005400 189/21369/0 gen 21 0 1 POP PEEK 
> [root@obiwan root]# cat /proc/net/mpls_out 
> 0x00000004 666/51158/0 2 PUSH(gen 22) SET(eth1,192.168.2.2) 
> [root@obiwan root]# /mnt/image/pkg/ip route add 192.168.2.2/32 via
> 192.168.2.2 lsp 0x00000004
> [root@obiwan root]# netstat -rn            
> Kernel IP Routentabelle
> Ziel         Router       Genmask      Flags   MSS Fenster irtt Iface
> 192.168.2.2   192.168.2.2   255.255.255.255 UGH     40 0    0 eth1
> 
> 
> Configuration of PC2:
> [root@amidala root]# cat /proc/net/mpls_labelspace 
> eth0	0	11
> [root@amidala root]# cat /proc/net/mpls_in         
> 0x40005800 738/59582/0 gen 22 0 1 POP PEEK 
> [root@amidala root]# cat /proc/net/mpls_out 
> 0x00000012 238/25613/0 2 PUSH(gen 21) SET(eth0,192.168.2.1) 
> [root@amidala root]# /mnt/image/pkg/ip route add 192.168.2.1/32 via
> 192.168.2.1 lsp 0x00000012
> [root@amidala root]# netstat -rn
> Kernel IP Routentabelle
> Ziel        Router        Genmask        Flags   MSS Fenster irtt Iface
> 192.168.2.1    192.168.2.1    255.255.255.255 UGH     40 0      0 eth0
> 
> --- config section stop ---
> 
> Now I tried to see, that I am really using MPLS. For that reason I have
> installed ethereal.
> 
> Now I have the following problems:
> 
> If I ping obiwan I get the following output of tethereal:
> 
> 2615.091161 02:01:08:00:36:94 -> c0:a8:02:02:c0:a8 0xb909 Ethernet II
> 2615.091215   obiwan-2-1 -> amidala      ICMP Echo (ping) reply
> 
> What the hell is 02:01:08:00:36:94? It looks like a MAC address, but we
> have no cards with these address.
> The answer of obiwan looks good. I had a look on it with ethereal and it
> looks like a "normal" mpls header.
> But the ping request is bad. With ethereal I saw, that there are 6
> MPLS-Headers are included. But why? I appended the output of ethereal.
> 
> The second thing is, that I am able to ping obiwan, but a traceroute to
> the same IP (only one hop of course) generates no output. I have to
> press cntl-c.
> [root@amidala root]# traceroute 192.168.2.1
> traceroute to 192.168.2.1 (192.168.2.1), 30 hops max, 38 byte packets
> 
> [root@amidala root]#
> 
> So whats wrong?
> Maybe I have patched the wrong version of iproute2?
> 
> 
> I hope someone can help me.
> Thanks.
> 
> Oliver
> 



-- 
James R. Leu

Re: [mpls-linux-general] Mpls installation problems with the new version.

[Oliver H. <ho...@tm...>]

Am Mit, 2002-07-31 um 17.53 schrieb James R. Leu:
> http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/mpls-linux/mpls-linux/NOTE=
?rev=3D1.5.2.2&only_with_tag=3Dmpls-linux_1_152&content-type=3Dtext/vnd.vie=
wcvs-markup
ok. That means, that MPLS is working well? Nice! :]
But why I am not able to let a traceroute running?
Ping works well, but traceroute has not output? (see mailing below)

>=20
> On Wed, Jul 31, 2002 at 04:35:47PM +0200, Oliver Horvath wrote:
> > Hi,
> >=20
> > I try to install a mpls network, in a first step with two PCs.
> > I use kernel 2.4.18 and the mpls version 1.152, July 27, 2002.
> >=20
> > PC1: obiwan (192.168.2.1)  <---> PC2: amidala (192.168.2.2)
> >=20
> > Each PC has a network card with 4 slots (to build up a bigger network
> > later).
> >=20
> > --- config section start ---
> >=20
> > Configuration of PC1:
> > Label 21 (push and send) and label 22 (receive and push)=20
> >=20
> > [root@obiwan root]# cat /proc/net/mpls_labelspace=20
> > eth1	0	12
> > [root@obiwan root]# cat /proc/net/mpls_in        =20
> > 0x40005400 189/21369/0 gen 21 0 1 POP PEEK=20
> > [root@obiwan root]# cat /proc/net/mpls_out=20
> > 0x00000004 666/51158/0 2 PUSH(gen 22) SET(eth1,192.168.2.2)=20
> > [root@obiwan root]# /mnt/image/pkg/ip route add 192.168.2.2/32 via
> > 192.168.2.2 lsp 0x00000004
> > [root@obiwan root]# netstat -rn           =20
> > Kernel IP Routentabelle
> > Ziel         Router       Genmask      Flags   MSS Fenster irtt Iface
> > 192.168.2.2   192.168.2.2   255.255.255.255 UGH     40 0    0 eth1
> >=20
> >=20
> > Configuration of PC2:
> > [root@amidala root]# cat /proc/net/mpls_labelspace=20
> > eth0	0	11
> > [root@amidala root]# cat /proc/net/mpls_in        =20
> > 0x40005800 738/59582/0 gen 22 0 1 POP PEEK=20
> > [root@amidala root]# cat /proc/net/mpls_out=20
> > 0x00000012 238/25613/0 2 PUSH(gen 21) SET(eth0,192.168.2.1)=20
> > [root@amidala root]# /mnt/image/pkg/ip route add 192.168.2.1/32 via
> > 192.168.2.1 lsp 0x00000012
> > [root@amidala root]# netstat -rn
> > Kernel IP Routentabelle
> > Ziel        Router        Genmask        Flags   MSS Fenster irtt Iface
> > 192.168.2.1    192.168.2.1    255.255.255.255 UGH     40 0      0 eth0
> >=20
> > --- config section stop ---
> >=20
> > Now I tried to see, that I am really using MPLS. For that reason I have
> > installed ethereal.
> >=20
> > Now I have the following problems:
> >=20
> > If I ping obiwan I get the following output of tethereal:
> >=20
> > 2615.091161 02:01:08:00:36:94 -> c0:a8:02:02:c0:a8 0xb909 Ethernet II
> > 2615.091215   obiwan-2-1 -> amidala      ICMP Echo (ping) reply
> >=20
> > What the hell is 02:01:08:00:36:94? It looks like a MAC address, but we
> > have no cards with these address.
> > The answer of obiwan looks good. I had a look on it with ethereal and i=
t
> > looks like a "normal" mpls header.
> > But the ping request is bad. With ethereal I saw, that there are 6
> > MPLS-Headers are included. But why? I appended the output of ethereal.
> >=20
> > The second thing is, that I am able to ping obiwan, but a traceroute to
> > the same IP (only one hop of course) generates no output. I have to
> > press cntl-c.
> > [root@amidala root]# traceroute 192.168.2.1
> > traceroute to 192.168.2.1 (192.168.2.1), 30 hops max, 38 byte packets
> >=20
> > [root@amidala root]#
> >=20
> > So whats wrong?
> > Maybe I have patched the wrong version of iproute2?
> >=20
> >=20
> > I hope someone can help me.
> > Thanks.
> >=20
> > Oliver
> >=20
>=20
>=20
>=20
> --=20
> James R. Leu
>=20
>=20
> -------------------------------------------------------
> This sf.net email is sponsored by: Dice - The leading online job board
> for high-tech professionals. Search and apply for tech jobs today!
> http://seeker.dice.com/seeker.epl?rel_code=3D31
> _______________________________________________
> mpls-linux-general mailing list
> mpl...@li...
> https://lists.sourceforge.net/lists/listinfo/mpls-linux-general
>=20
--=20
Dipl.-Inf. Oliver Horvath          Johann Wolfgang Goethe-Universit=E4t
Tel: 069/798-28358 (Fax: 23340)   Institut f=FCr Informatik - Telematik

Re: [mpls-linux-general] Mpls installation problems with the new version.

[James R. L. <jl...@mi...>]

On Wed, Jul 31, 2002 at 05:07:04PM +0200, Oliver Horvath wrote:
> Am Mit, 2002-07-31 um 17.53 schrieb James R. Leu:
> > http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/mpls-linux/mpls-linux/=
NOTE?rev=3D1.5.2.2&only_with_tag=3Dmpls-linux_1_152&content-type=3Dtext/v=
nd.viewcvs-markup
> ok. That means, that MPLS is working well? Nice! :]
> But why I am not able to let a traceroute running?
> Ping works well, but traceroute has not output? (see mailing below)

Handling of packets with TTL <=3D 1 is broken right now.  The result is t=
hat the
packet gets dropped.  I think I know how I'm going to handle it:

Check if this is the botton of the stack, if not drop the packet.
Check the protocol associated with the ILM, if it is not IP, drop it.
If it is IP, generate an ICMP message, and forward it along the LSP, the
egress can deal with the ICMP message.

There is probably a special case where it is the egress of the LSP that
finds a TTL <=3D 1 that needs to be handled differntly.  Besides that,
does this sound like the right behavior?

Jim

>=20
> >=20
> > On Wed, Jul 31, 2002 at 04:35:47PM +0200, Oliver Horvath wrote:
> > > Hi,
> > >=20
> > > I try to install a mpls network, in a first step with two PCs.
> > > I use kernel 2.4.18 and the mpls version 1.152, July 27, 2002.
> > >=20
> > > PC1: obiwan (192.168.2.1)  <---> PC2: amidala (192.168.2.2)
> > >=20
> > > Each PC has a network card with 4 slots (to build up a bigger netwo=
rk
> > > later).
> > >=20
> > > --- config section start ---
> > >=20
> > > Configuration of PC1:
> > > Label 21 (push and send) and label 22 (receive and push)=20
> > >=20
> > > [root@obiwan root]# cat /proc/net/mpls_labelspace=20
> > > eth1	0	12
> > > [root@obiwan root]# cat /proc/net/mpls_in        =20
> > > 0x40005400 189/21369/0 gen 21 0 1 POP PEEK=20
> > > [root@obiwan root]# cat /proc/net/mpls_out=20
> > > 0x00000004 666/51158/0 2 PUSH(gen 22) SET(eth1,192.168.2.2)=20
> > > [root@obiwan root]# /mnt/image/pkg/ip route add 192.168.2.2/32 via
> > > 192.168.2.2 lsp 0x00000004
> > > [root@obiwan root]# netstat -rn           =20
> > > Kernel IP Routentabelle
> > > Ziel         Router       Genmask      Flags   MSS Fenster irtt Ifa=
ce
> > > 192.168.2.2   192.168.2.2   255.255.255.255 UGH     40 0    0 eth1
> > >=20
> > >=20
> > > Configuration of PC2:
> > > [root@amidala root]# cat /proc/net/mpls_labelspace=20
> > > eth0	0	11
> > > [root@amidala root]# cat /proc/net/mpls_in        =20
> > > 0x40005800 738/59582/0 gen 22 0 1 POP PEEK=20
> > > [root@amidala root]# cat /proc/net/mpls_out=20
> > > 0x00000012 238/25613/0 2 PUSH(gen 21) SET(eth0,192.168.2.1)=20
> > > [root@amidala root]# /mnt/image/pkg/ip route add 192.168.2.1/32 via
> > > 192.168.2.1 lsp 0x00000012
> > > [root@amidala root]# netstat -rn
> > > Kernel IP Routentabelle
> > > Ziel        Router        Genmask        Flags   MSS Fenster irtt I=
face
> > > 192.168.2.1    192.168.2.1    255.255.255.255 UGH     40 0      0 e=
th0
> > >=20
> > > --- config section stop ---
> > >=20
> > > Now I tried to see, that I am really using MPLS. For that reason I =
have
> > > installed ethereal.
> > >=20
> > > Now I have the following problems:
> > >=20
> > > If I ping obiwan I get the following output of tethereal:
> > >=20
> > > 2615.091161 02:01:08:00:36:94 -> c0:a8:02:02:c0:a8 0xb909 Ethernet =
II
> > > 2615.091215   obiwan-2-1 -> amidala      ICMP Echo (ping) reply
> > >=20
> > > What the hell is 02:01:08:00:36:94? It looks like a MAC address, bu=
t we
> > > have no cards with these address.
> > > The answer of obiwan looks good. I had a look on it with ethereal a=
nd it
> > > looks like a "normal" mpls header.
> > > But the ping request is bad. With ethereal I saw, that there are 6
> > > MPLS-Headers are included. But why? I appended the output of ethere=
al.
> > >=20
> > > The second thing is, that I am able to ping obiwan, but a tracerout=
e to
> > > the same IP (only one hop of course) generates no output. I have to
> > > press cntl-c.
> > > [root@amidala root]# traceroute 192.168.2.1
> > > traceroute to 192.168.2.1 (192.168.2.1), 30 hops max, 38 byte packe=
ts
> > >=20
> > > [root@amidala root]#
> > >=20
> > > So whats wrong?
> > > Maybe I have patched the wrong version of iproute2?
> > >=20
> > >=20
> > > I hope someone can help me.
> > > Thanks.
> > >=20
> > > Oliver
> > >=20
> >=20
> >=20
> >=20
> > --=20
> > James R. Leu
> >=20
> >=20
> > -------------------------------------------------------
> > This sf.net email is sponsored by: Dice - The leading online job boar=
d
> > for high-tech professionals. Search and apply for tech jobs today!
> > http://seeker.dice.com/seeker.epl?rel_code=3D31
> > _______________________________________________
> > mpls-linux-general mailing list
> > mpl...@li...
> > https://lists.sourceforge.net/lists/listinfo/mpls-linux-general
> >=20
> --=20
> Dipl.-Inf. Oliver Horvath          Johann Wolfgang Goethe-Universit=E4t
> Tel: 069/798-28358 (Fax: 23340)   Institut f=FCr Informatik - Telematik
>=20
>=20
>=20
> -------------------------------------------------------
> This sf.net email is sponsored by: Dice - The leading online job board
> for high-tech professionals. Search and apply for tech jobs today!
> http://seeker.dice.com/seeker.epl?rel_code1
> _______________________________________________
> mpls-linux-general mailing list
> mpl...@li...
> https://lists.sourceforge.net/lists/listinfo/mpls-linux-general

--=20
James R. Leu

Re: [mpls-linux-general] Mpls installation problems with the new version.

[Oliver H. <ho...@tm...>]

Am Mit, 2002-07-31 um 18.21 schrieb James R. Leu:
> On Wed, Jul 31, 2002 at 05:07:04PM +0200, Oliver Horvath wrote:
> > Am Mit, 2002-07-31 um 17.53 schrieb James R. Leu:
> > > http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/mpls-linux/mpls-linux/NOTE?rev=1.5.2.2&only_with_tag=mpls-linux_1_152&content-type=text/vnd.viewcvs-markup
> > ok. That means, that MPLS is working well? Nice! :]
> > But why I am not able to let a traceroute running?
> > Ping works well, but traceroute has not output? (see mailing below)
> 
> Handling of packets with TTL <= 1 is broken right now.  The result is that the
> packet gets dropped.  I think I know how I'm going to handle it:
> 
> Check if this is the botton of the stack, if not drop the packet.
> Check the protocol associated with the ILM, if it is not IP, drop it.
> If it is IP, generate an ICMP message, and forward it along the LSP, the
> egress can deal with the ICMP message.
> 
> There is probably a special case where it is the egress of the LSP that
> finds a TTL <= 1 that needs to be handled differntly.  Besides that,
> does this sound like the right behavior?

Sounds good for me.

I tested ethereal in the middle of a lsp (no edge router) and there it
works well.
Do you have a idea, if there is a chance to monitor the edge routers
correctly too?
I defined a wrong outgoing lable on a edge router, and I saw two things:
a) Ping is still working, but why? If mpls didn't know the incoming
label, it pops the label off and tries to find a working label in the
outgoing labels? Or is the label poped off and forwarded by normal ip?
b) Tracerout stops at the middle of the lsp (3 PCs). Why it is not
forwarded like the pings?

Oliver

Re: [mpls-linux-general] Mpls installation problems with the new version.

[James R. L. <jl...@mi...>]

> > Handling of packets with TTL <= 1 is broken right now.  The result is that the
> > packet gets dropped.  I think I know how I'm going to handle it:
> > 
> > Check if this is the botton of the stack, if not drop the packet.
> > Check the protocol associated with the ILM, if it is not IP, drop it.
> > If it is IP, generate an ICMP message, and forward it along the LSP, the
> > egress can deal with the ICMP message.
> > 
> > There is probably a special case where it is the egress of the LSP that
> > finds a TTL <= 1 that needs to be handled differntly.  Besides that,
> > does this sound like the right behavior?
> 
> Sounds good for me.
> 
> I tested ethereal in the middle of a lsp (no edge router) and there it
> works well.
> Do you have a idea, if there is a chance to monitor the edge routers
> correctly too?

For this to work correctly I would have to make a complete copy of the
packet and modify the copy, not the original. This would be slow, so I
don't want to do it as part of the normal path.  If people would really
like to see "correct" MPLS packets at the LERs maybe I can figure out
a way to tell if someone else has a handle to the packet and change the path
accordingly.

If you would like a detailed description of why it workes the way it
does I can walk you through the code.

> I defined a wrong outgoing lable on a edge router, and I saw two things:
> a) Ping is still working, but why? If mpls didn't know the incoming
> label, it pops the label off and tries to find a working label in the
> outgoing labels? Or is the label poped off and forwarded by normal ip?

I haven't done any negative testing recently, I will try your test tonight.
It shouldn't have worked.

> b) Tracerout stops at the middle of the lsp (3 PCs). Why it is not
> forwarded like the pings?

*shrug* Let me figure out what the ping _worked_ first :-)

Jim

-- 
James R. Leu