Re: [mpls-linux-general] Re:Re: help: how to ssh to mpls machine?
Status: Beta
Brought to you by:
jleu
Menu
▾
▴
Re: [mpls-linux-general] Re:Re: help: how to ssh to mpls machine?
|
From: mu2000 <mu...@gm...> - 2005-03-28 12:24:22
|
Thanks a lot for the detailed setup example. The problem still remains though, namely, A ssh to ulm1, ulm2 ulm3, etc. is Okay. But ulm1 cannot ssh to ulm2, ulm1 cannot ssh to ulm2, ulm2 cannot ssh to ulm3, etc. The same problem occurs whether I have setup the LSP from ulm4 to ulm1 or not. ssh among the A, ulm1, ulm2, ulm3, ulm4 and B has no problem without mpls. Not really crucial to my mpls network. But I still would like to know why this happens. Any hint appreciated. Also the throughput of the mpls network is really slow (a few k in a 10M ethernet, a few M in a 100M ethernet, with mpls debug in all PC turned off), tested with netperf and meansured traffic (tg (a traffic generator) and tcpdump/tcptrace). Thanks a lot for the nice work in any case. morris On Mon, 14 Mar 2005 20:26:17 -0600, James R. Leu <jl...@mi...> wrote: > > I'm going to add some numbers to the drawing above and then create the > full set of commands that you will need to issue. You should be able to > extrapolate from that. > > 1.1.1.0/24 3.3.1.0/24 3.3.2.0/24 3.3.3.0/24 2.2.2.0/24 > .1 .2 .1 .2 .1 .2 .1 .2 .1 .2 > e1 e2 e1 e2 e1 e2 e1 e2 e1 e2 > L0 L1 L2 L3 L4 > |A|--------|ulm1|--------|ulm2|--------|ulm3|--------|ulm4|--------|B| > -----1000----X-----1100----X-----1200----> > <----2000----X-----2100----X-----2200----- > > 'X' denotes label swap > > A > ----- > ip route add 2.2.2.0/24 via 1.1.1.2 advmss 1400 > > ulm1 > ---- > mpls nhlfe add key 0 instructions push gen 1000 nexthop eth1 ipv4 3.3.1.2 > (key 0x2) > ip route add 2.2.2.0/24 via 3.3.1.2 spec_nh 0x8847 0x2 advmss 1400 > > mpls labelspace add dev eth1 labelspace 0 > mpls ilm add label gen 2000 labelspace 0 > > ulm2 > ---- > mpls labelspace add dev eth2 labelspace 0 > mpls ilm add label gen 1000 labelspace 0 > mpls nhlfe add key 0 instructions push gen 1100 nexthop eth1 ipv4 3.3.2.2 > (key 0x2) > mpls xc add ilm_label gen 1000 ilm_labelspace 0 nhlfe key 0x2 > > mpls labelspace add dev eth1 labelspace 0 > mpls ilm add label gen 2100 labelspace 0 > mpls nhlfe add key 0 instructions push gen 2000 nexthop eth2 ipv4 3.3.1.1 > (key 0x3) > mpls xc add ilm_label gen 2100 ilm_labelspace 0 nhlfe key 0x3 > > ulm3 > ---- > mpls labelspace add dev eth2 labelspace 0 > mpls ilm add label gen 1100 labelspace 0 > mpls nhlfe add key 0 instructions push gen 1200 nexthop eth1 ipv4 3.3.3.2 > (key 0x2) > mpls xc add ilm_label gen 1100 ilm_labelspace 0 nhlfe key 0x2 > > mpls labelspace add dev eth1 labelspace 0 > mpls ilm add label gen 2200 labelspace 0 > mpls nhlfe add key 0 instructions push gen 2100 nexthop eth2 ipv4 3.3.2.1 > (key 0x3) > mpls xc add ilm_label gen 2200 ilm_labelspace 0 nhlfe key 0x3 > > ulm4 > ---- > mpls labelspace add dev eth2 labelspace 0 > mpls ilm add label gen 1200 labelspace 0 > > mpls nhlfe add key 0 instructions push gen 2200 nexthop eth2 ipv4 3.3.3.1 > (key 0x3) > ip route add 1.1.1.0/24 via 3.3.3.1 spec_nh 0x8847 0x3 advmss 1400 > > B > ----- > ip route add 1.1.1.0/24 via 2.2.2.1 advmss 1400 > > If you have ethernet cards which can support jumbo frames then you can > remove the advmss part and increase the MTU on L1,L2,L3 to 9000 > > Note that I did not add any routes IP routes to ulm2 or ulm3, and only > the 1.1.1.0/24 and 2.2.2.0/24 routes to ulm4 and ulm1 (respectivly). > > > I'll try to capture the normal traffic and send it the list. > > Just make sure you don't waste time, I'd like to see that same packet as > is moves from L0 to L1 or from L3 to L4. > > > > > Thanks, > > morris > > > > > > On Mon, 14 Mar 2005 13:36:46 -0600, James R. Leu <jl...@mi...> wrote: > > > > > On Sun, Mar 13, 2005 at 12:21:17PM +0800, mu w wrote: > > > > > > > > Thanks for taking the time to reply, James. > > > > > > Are you using TCP offload cards? Did you compiling your own kernel > > > or did you use an RPM? > > > > > > > Yes I can ssh to ulm3 when MPLS is not enabled. The MTU between ulm2 and > > > > ulm3 are 1500 (showed by `ip link or ip add`) and 1494 shown by `mpls > > > > nhlfe show`. The set up commands for mpls: > > > > > > Try setting the advmss on the routes for you ingress/egress. > > > How are you setting up the routes on ingress egress? > > > > > > > > > > > outgoing labels on bother interfaces: mpls nhlfe add key/ mpls nhlfe > > > > change key KEY_PREVIOUSLY_GENERATED ... > > > > incoming labels on both interfaces: mpls labelspace add dev DEV > > > > labelspace 0/mpls ilm add label gen LABEL(match with incoming label) > > > > labelspace 0 > > > > (Do I need to use xc? > > > > But ping works Okay, all request and reply are mpls enabled -- I see the > > > > mpls bits in ethereal and tcpdump) > > > > > > Are any of your devices just a LSR, ie it should only see labeled packets? > > > If so then yes, otherwise no :-) > > > > > > > If I use 'telnet ulm3 22', I see the initial response: > > > > Connected to 192.168.25.1. > > > > Escape character is '^]'. > > > > SSH-1.99-OpenSSH_3.6.1p2 > > > > > > > > I have done some more testing with ethereal and tcpdump. In one of the > > > > ethereal outputs, I can see the three-way handshake is complete, > > > > then ulm3 three sends a [SYN, FIN, ACK, CWR] to ulm1. The ethereal > > > > says "Header length: 16 bytes (bogus, must be at least 20)" shown below: > > > > > > Can you capture the same packet on the IP only link and then the > > > MPLS link and do a full HEX dump of it and send it to the mailing list? > > > > > > > [frames 2,3,4, threeway handshake, no problem] > > > > Frame 5 (95 bytes on wire, 95 bytes captured) > > > > Ethernet II, Src: 00:02:44:6a:ff:f8, Dst: 00:50:04:c3:7a:40 > > > > MultiProtocol Label Switching Header > > > > Internet Protocol, Src Addr: 192.168.13.2 (192.168.13.2), Dst Addr: > > > > 192.168.25.1 (192.168.25.1) > > > > Transmission Control Protocol, Src Port: ssh (22), Dst Port: 1139 > > > > (1139), Seq: 0 > > > > Source port: ssh (22) > > > > Destination port: 1139 (1139) > > > > Sequence number: 0 > > > > Header length: 16 bytes (bogus, must be at least 20) > > > > > > > > Frame 6 (95 bytes on wire, 95 bytes captured) > > > > Ethernet II, Src: 00:02:44:6a:ff:f8, Dst: 00:50:04:c3:7a:40 > > > > MultiProtocol Label Switching Header > > > > Internet Protocol, Src Addr: 192.168.13.2 (192.168.13.2), Dst Addr: > > > > 192.168.25.1 (192.168.25.1) > > > > Transmission Control Protocol, Src Port: ssh (22), Dst Port: 1139 > > > > (1139), Seq: 0 > > > > Source port: ssh (22) > > > > Destination port: 1139 (1139) > > > > Sequence number: 0 > > > > Header length: 16 bytes (bogus, must be at least 20) > > > > ... > > > > > > > > > > > > From some tcpdump output, it looks like the checksum sometimes goes bad > > > > -- "bad tcp checksum a792 (->59c2)!" in the following tcpdump output. > > > > > > > > Thanks, > > > > morris > > > > > > > > `tcp -xvp -i eth0` output > > > > > > > > 11:47:32.828060 MPLS (label 25, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 45153, offset 0, flags [DF], proto 6, > > > > length: 60) 192.168.25.1.1138 > 192.168.13.1.ssh: S [tcp sum ok] > > > > 3559799760:3559799760(0) win 5840 <mss 1460,sackOK,timestamp 89820081 > > > > 0,nop,wscale 2> > > > > 0x0000: 0001 9140 4500 003c b061 4000 4006 e307 ...@E..<.a@.@... > > > > 0x0010: c0a8 1901 c0a8 0d01 0472 0016 d42e 3bd0 .........r....;. > > > > 0x0020: 0000 0000 a002 16d0 e44f 0000 0204 05b4 .........O...... > > > > 0x0030: 0402 080a 055a 8bb1 0000 0000 0103 0302 .....Z.......... > > > > 11:47:32.828813 MPLS (label 125, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto 6, > > > > length: 60) 192.168.13.1.ssh > 192.168.25.1.1138: S [tcp sum ok] > > > > 2832248515:2832248515(0) ack 3559799761 win 5792 <mss > > > > 1460,sackOK,timestamp 153217841 89820081,nop,wscale 2> > > > > 0x0000: 0007 d140 4500 003c 0000 4000 4006 9369 ...@E..<..@.@..i > > > > 0x0010: c0a8 0d01 c0a8 1901 0016 0472 a8d0 aec3 ...........r.... > > > > 0x0020: d42e 3bd1 a012 16a0 9887 0000 0204 05b4 ..;............. > > > > 0x0030: 0402 080a 0921 eb31 055a 8bb1 0103 0302 .....!.1.Z...... > > > > 11:47:32.829452 MPLS (label 25, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 45155, offset 0, flags [DF], proto 6, > > > > length: 52) 192.168.25.1.1138 > 192.168.13.1.ssh: . [tcp sum ok] ack 1 > > > > win 1460 <nop,nop,timestamp 89820083 153217841> > > > > 0x0000: 0001 9140 4500 0034 b063 4000 4006 e30d ...@E..4.c@.@... > > > > 0x0010: c0a8 1901 c0a8 0d01 0472 0016 d42e 3bd1 .........r....;. > > > > 0x0020: a8d0 aec4 8010 05b4 d838 0000 0101 080a .........8...... > > > > 0x0030: 055a 8bb3 0921 eb31 .Z...!.1 > > > > 11:47:32.832443 MPLS (label 125, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 17910, offset 0, flags [DF], proto 6, > > > > length: 77) 192.168.13.1.ssh > 192.168.25.1.1138: FE [bad tcp cksum a792 > > > > (->59c2)!] 1:34(33) ack 1 win 1448 urg 0 <nop,nop,[bad opt]> > > > > 0x0000: 0007 d140 4500 004d 45f6 4000 4006 4d62 ...@E..ME.@.@.Mb > > > > 0x0010: c0a8 0d01 c0a8 1901 0016 0472 a8d0 aec4 ...........r.... > > > > 0x0020: d42e 3bd1 6371 05a8 a792 0000 0101 080a ..;.cq.......... > > > > 0x0030: 0921 eb34 055a 8bb3 5353 482d 312e 3939 .!.4.Z..SSH-1.99 > > > > 0x0040: 2d4f 7065 6e53 5348 5f33 2e36 2e31 7032 -OpenSSH_3.6.1p2 > > > > 0x0050: 0a > > > > 11:47:33.033583 MPLS (label 125, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 17912, offset 0, flags [DF], proto 6, > > > > length: 77) 192.168.13.1.ssh > 192.168.25.1.1138: SFRW [bad tcp cksum > > > > a792 (->59c2)!] 2832248516:2832248549(33) win 1448 urg 0 <nop,nop,[bad opt]> > > > > 0x0000: 0007 d140 4500 004d 45f8 4000 4006 4d60 ...@E..ME.@.@.M` > > > > 0x0010: c0a8 0d01 c0a8 1901 0016 0472 a8d0 aec4 ...........r.... > > > > 0x0020: d42e 3bd1 62a7 05a8 a792 0000 0101 080a ..;.b........... > > > > 0x0030: 0921 ebfe 055a 8bb3 5353 482d 312e 3939 .!...Z..SSH-1.99 > > > > 0x0040: 2d4f 7065 6e53 5348 5f33 2e36 2e31 7032 -OpenSSH_3.6.1p2 > > > > 0x0050: 0a . > > > > 11:47:33.435402 MPLS (label 125, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 17914, offset 0, flags [DF], proto 6, > > > > length: 77) 192.168.13.1.ssh > 192.168.25.1.1138: FR [bad tcp cksum a792 > > > > (->59c2)!] 1:34(33) ack 1 win 1448 <nop,nop,[bad opt]> > > > > 0x0000: 0007 d140 4500 004d 45fa 4000 4006 4d5e ...@E..ME.@.@.M^ > > > > 0x0010: c0a8 0d01 c0a8 1901 0016 0472 a8d0 aec4 ...........r.... > > > > 0x0020: d42e 3bd1 6115 05a8 a792 0000 0101 080a ..;.a........... > > > > 0x0030: 0921 ed90 055a 8bb3 5353 482d 312e 3939 .!...Z..SSH-1.99 > > > > 0x0040: 2d4f 7065 6e53 5348 5f33 2e36 2e31 7032 -OpenSSH_3.6.1p2 > > > > 0x0050: 0a . > > > > 11:47:34.239254 MPLS (label 125, exp 0, [S], ttl 64) > > > > IP (tos 0x0, ttl 64, id 17916, offset 0, flags [DF], proto 6, > > > > length: 77) 192.168.13.1.ssh > 192.168.25.1.1138: FWE [bad tcp cksum > > > > a792 (->59c2)!] 1:38(37) ack 1 win 1448 urg 0 > > > > 0x0000: 0007 d140 4500 004d 45fc 4000 4006 4d5c ...@E..ME.@.@.M\ > > > > 0x0010: c0a8 0d01 c0a8 1901 0016 0472 a8d0 aec4 ...........r.... > > > > 0x0020: d42e 3bd1 5df1 05a8 a792 0000 0101 080a ..;.]........... > > > > 0x0030: 0921 f0b4 055a 8bb3 5353 482d 312e 3939 .!...Z..SSH-1.99 > > > > 0x0040: 2d4f 7065 6e53 5348 5f33 2e36 2e31 7032 -OpenSSH_3.6.1p2 > > > > 0x0050: 0a . > > > > 11:47:35.669679 IP (tos 0xc0, ttl 1, id 58574, offset 0, flags [none], > > > > proto 89, length: 68) 192.168.25.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello > > > > (1), length: 48 > > > > Router-ID: 192.168.25.2, Area 0.0.0.100, Authentication Type: > > > > none (0) > > > > Options: [External] > > > > Hello Timer: 10s, Dead Timer 40s, Mask: 255.255.255.0, Priority: 1 > > > > Designated Router 192.168.25.2, Backup Designated Router > > > > 192.168.25.1 > > > > Neighbor List: > > > > 192.168.88.2 > > > > 0x0000: 45c0 0044 e4ce 0000 0159 1a23 c0a8 1902 E..D.....Y.#.... > > > > 0x0010: e000 0005 0201 0030 c0a8 1902 0000 0064 .......0.......d > > > > 0x0020: 568c 0000 0000 0000 0000 0000 ffff ff00 V............... > > > > 0x0030: 000a 0201 0000 0028 c0a8 1902 c0a8 1901 .......(........ > > > > 0x0040: c0a8 5802 > > > > > > > > > > > > > > > > > > > > ======================================= > > > > From: James R. Leu <jleu@mi...> > > > > * Re: help: how to ssh to mpls machine?* > > > > <http://sourceforge.net/mailarchive/message.php?msg_id=11144914> > > > > 2005-03-12 17:43 > > > > > > > > > > > > > > > > > > > > Can you ssh to the machine in question when MPLS is not enabled > > > > in the network? What are the exact commands you issuesd on all of machines > > > > in your diagram? What is the MTU of the link between ulm2 and ulm3? > > > > > > > > On Sun, Mar 13, 2005 at 12:39:22AM +0800, mu w wrote: > > > > > (ssh to non-mpls machines via mpls net works) -- one more time > > > > > > > > > > OK the previous email didn"t get through...please forgive me for > > > > reposting. > > > > > > > > > > Hi James and all... > > > > > > > > > > I built an mpls network using static label switched path, by using mpls > > > > > nhlfe...and mpls ilm...etc (in 2.6.9-1.6_FC2mpls_1_946). Everything > > > > > works fine except I cannot ssh to an mpls machine. > > > > > The following figure show my network > > > > > > > > > > ulm1--ulm2---ulm3----ulm4 > > > > > > > > > > ulm2 and ulm3 are the mpls network, ulm1 and ulm4 are normal IP hosts. > > > > > ulm1 can ssh to ulm4 (traffic on ulm2 and ulm3 are labeled) but cannot > > > > > ssh to ulm3. ping to ulm3 is okay. > > > > > > > > > > Ethereal shows the mpls traffic for ssh handshake...SYN and stuff but > > > > > the connection was reset after a while. > > > > > > > > > > Is ssh to ulm3 possible? If yes how to setup? > > > > > > > > > > I have seen question on ftp and ssh questions in the archive but can"t > > > > > find any answers. Any help and pointer are appreciated. > > > > > > > > > > Also, is there a more detailed manual for the mpls command in (uname -a > > > > > = 2.6.9-1.6_FC2mpls_1_946)? > > > > > > > > Not written yet, but you can issue "mpls help" and it will give you > > > > command line syntax. > > > > > > > > > > > > > > > > > > > > ------------------------------------------------------- > > > > SF email is sponsored by - The IT Product Guide > > > > Read honest & candid reviews on hundreds of IT Products from real users. > > > > Discover which products truly live up to the hype. Start reading now. > > > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > > > _______________________________________________ > > > > mpls-linux-general mailing list > > > > mpl...@li... > > > > https://lists.sourceforge.net/lists/listinfo/mpls-linux-general > > > > > > -- > > > James R. Leu > > > jl...@mi... > > > > > > > > > > > > > > > ------------------------------------------------------- > > SF email is sponsored by - The IT Product Guide > > Read honest & candid reviews on hundreds of IT Products from real users. > > Discover which products truly live up to the hype. Start reading now. > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > _______________________________________________ > > mpls-linux-general mailing list > > mpl...@li... > > https://lists.sourceforge.net/lists/listinfo/mpls-linux-general > > -- > James R. Leu > jl...@mi... > > > |
