You are getting very strange results indeed, but what you're tying to do is somewhat strange too. It seems that you are tying to get two parallel serial links to work:
R1 s0 ----- s0 R2 R1 s1 ----- s1 R2 Are you sure that both 4000M routers support two active serial interfaces? I would start by simplifying the tests. Does this work? R1 s0 ----- s0 R2 If yes, using the exact same cable, see if this works: R1 s1 ----- s1 R2 How about this (with the exact same cable): R1 s0 ------ s1 R2 And this: R1 s1 ------ s0 R2 OK, now try all these tests with the other cable. Do they fail? It sure seems like it could be a bad cable, although you said you swapped cables... Once you confirm that single links work, then try the parallel links. If they don't work, at least you have some data as to what causes the problem. My suspicion is that you'll have a problem even on a single link though. I'm suspicious of Router 2's Serial 0's receive capabilities. You say that on Router 1 you're seeing: Serial0: HDLC myseq 18, mineseen 0*, yourseen 18, line down. This indicates that Router 1 is sending keepalives (or at least thinks that it is.) But Router 1 is not seeing ACKs from Router 2. Router 1 is seeing (or at least at one point saw) 18 keepalives from Router 2. So Router 2 can transmit. Maybe Router 2 can't receive though, which would explain it's not ACKing. On Router 2, you're seeing: Serial0: HDLC myseq 42, mineseen 0, yourseen 0, line down. This indicates that Router 2 is transmitting keepalives (or at least thinks that it is). But Router 2 is not seeing ACKs or keepalives from the other side. Could Router 2's Serial 0 interface be bad (unable to receive?) A bad cable could also cause this problem. Sorry, I can't give you more advice. Please let us know what you find out. Thanks. Priscilla At 02:33 PM 2/25/02, [EMAIL PROTECTED] wrote: >Hello all: > >I have two Cisco 4000-M routers in my home lab with two serial ports on >each. S0 on Router 1 is connected to S0 on Router 2. S1 on Router 1 is >connected to S1 on Router 2. The problem is that the S1 to S1 link comes up >and stays up. The S0 to S0 link comes up but goes down in a few seconds. It >keeps going up and down in this way repeatedly. Could someone please shed >some light? > >The routers are connected using DCE to DTE cross connect cables. The DCE >ends of both connections are on Router 2 and it providing clocking at 56000 >bits per second. Encapsulation is HDLC although I have tried PPP with the >same problem. I have also tried changing the default keepalive settings on >both end on the S0 to SO link. The IOS is 12.1(12) on both. I have tried >12.1(10) with the same results. I have also tried changing the end where the >clocking is provided with no success. I have switched cables and serial >interface modules but the problem remains. > >Config on Router 1: >interface Serial0 > ip address 1.1.1.1 255.255.255.0 >! >interface Serial1 > ip address 2.2.2.1 255.255.255.0 >! >Log entries on Router 1: >Feb 25 17:59:41: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to up >Feb 25 18:00:01: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to down >Feb 25 18:00:11: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to up >Feb 25 18:00:31: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to down > >SH IP INTERFACE BRIEF on Router 1: >Interface IP-Address OK? Method Status >Protocol >Serial0 1.1.1.1 YES NVRAM up >down >Serial1 2.2.2.1 YES NVRAM up >up > >R1#sh control serial 0 >MK5 unit 0, NIM slot 1, NIM type code 7, NIM version 1 >idb = 0x619DACBC, driver structure at 0x619E10C0, regaddr = 0x3C100300 >IB at 0x400FB1CC: mode=0x0108, local_addr=0, remote_addr=0 >N1=1524, N2=1, scaler=100, T1=1000, T3=2000, TP=1 >buffer size 1524 >DTE V.35 serial cable attached > >DEBUG SERIAL INTERFACE on Router 1 >Feb 25 18:26:31: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to down >Feb 25 18:26:40: MK5(0): New serial state = 0xA104 >Feb 25 18:26:40: MK5(0): DCD is up. >Feb 25 18:26:40: Serial0: HDLC myseq 16, mineseen 0*, yourseen 16, line up >Feb 25 18:26:41: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to up >Feb 25 18:26:50: MK5(0): New serial state = 0x8104 >Feb 25 18:26:50: MK5(0): DCD is up. >Feb 25 18:26:50: MK5(0): Deasserting DTR >Feb 25 18:26:50: MK5(0): Deasserting DTR >Feb 25 18:26:50: MK5(0): Reset >Feb 25 18:26:50: MK5(0): Asserting DTR >Feb 25 18:26:50: MK5(0): Deasserting LTST >Feb 25 18:26:50: MK5(0): New serial state = 0xA105 >Feb 25 18:26:50: MK5(0): DCD is up. >Feb 25 18:26:50: Serial0: HDLC myseq 17, mineseen 0*, yourseen 17, line up >Feb 25 18:26:56: MK5(0): New serial state = 0xA124 >Feb 25 18:26:56: MK5(0): DCD is up. >Feb 25 18:26:56: MK5(0): New serial state = 0xA13C >Feb 25 18:26:56: MK5(0): DCD is down. >Feb 25 18:26:56: MK5(0): New serial state = 0xA134 >Feb 25 18:26:56: MK5(0): DCD is down. >Feb 25 18:26:56: MK5(0): New serial state = 0xA114 >Feb 25 18:26:56: MK5(0): DCD is down. >Feb 25 18:26:56: MK5(0): New serial state = 0xA104 >Feb 25 18:26:56: MK5(0): DCD is up. >Feb 25 18:27:00: MK5(0): New serial state = 0xA104 >Feb 25 18:27:00: MK5(0): DCD is up. >Feb 25 18:27:00: MK5(0): Deasserting DTR >Feb 25 18:27:00: MK5(0): Deasserting DTR >Feb 25 18:27:00: MK5(0): Reset >Feb 25 18:27:00: MK5(0): Asserting DTR >Feb 25 18:27:00: MK5(0): Deasserting LTST >Feb 25 18:27:00: MK5(0): New serial state = 0xA105 >Feb 25 18:27:00: MK5(0): DCD is up. >Feb 25 18:27:00: Serial0: HDLC myseq 18, mineseen 0*, yourseen 18, line down > >Feb 25 18:27:01: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, >changed state to down > > >Config on router 2: >interface Serial0 > ip address 1.1.1.2 255.255.255.0 > clockrate 56000 >! >interface Serial1 > ip address 2.2.2.2 255.255.255.0 > clockrate 56000 > >Log entries on Router 2: >None > >SH IP INTERFACE BRIEF on Router 2: >R2#sh ip int brief >Interface IP-Address OK? Method Status >Protocol >Serial0 1.1.1.2 YES NVRAM up >down >Serial1 2.2.2.2 YES NVRAM up >up > >R2#sh controller s 0 >MK5 unit 0, NIM slot 0, NIM type code 7, NIM version 1 >idb = 0x44A4, driver structure at 0xABDAB8, regaddr = 0x8000300 >IB at 0x6006E64: mode=0x0108, local_addr=0, remote_addr=0 >N1=1524, N2=1, scaler=100, T1=1000, T3=2000, TP=1 >buffer size 1524 >DCE V.35 serial cable attached, clockrate 56000 > >DEBUG SERIAL INTERFACE on Router 2: >Feb 25 18:30:25: Serial0: HDLC myseq 38, mineseen 0, yourseen 0, line down >.Feb 25 18:30:26: Serial0: attempting to restart >.Feb 25 18:30:26: MK5(0): Deasserting DSR >.Feb 25 18:30:26: MK5(0): Deasserting DSR >.Feb 25 18:30:26: MK5(0): Reset >.Feb 25 18:30:26: MK5(0): Asserting DSR >.Feb 25 18:30:26: MK5(0): Deasserting LTST >.Feb 25 18:30:26: MK5(0): Asserting DCD >.Feb 25 18:30:26: MK5(0): New serial state = 0x6017 >.Feb 25 18:30:26: MK5(0): DTR is up. >.Feb 25 18:30:30: MK5(0): New serial state = 0x603E >.Feb 25 18:30:30: MK5(0): DTR is down. >.Feb 25 18:30:30: MK5(0): New serial state = 0x6016 >.Feb 25 18:30:30: MK5(0): DTR is up. >.Feb 25 18:30:35: MK5(0): New serial state = 0x6016 >.Feb 25 18:30:35: MK5(0): DTR is up. >.Feb 25 18:30:35: Serial0: HDLC myseq 39, mineseen 0, yourseen 0, line down >.Feb 25 18:30:45: MK5(0): New serial state = 0x6016 >.Feb 25 18:30:45: MK5(0): DTR is up. >.Feb 25 18:30:45: Serial0: HDLC myseq 40, mineseen 0, yourseen 0, line down >.Feb 25 18:30:50: MK5(0): New serial state = 0x6036 >.Feb 25 18:30:50: MK5(0): DTR is down. >.Feb 25 18:30:50: MK5(0): New serial state = 0x6016 >.Feb 25 18:30:50: MK5(0): DTR is up. >.Feb 25 18:30:55: MK5(0): New serial state = 0x6016 >.Feb 25 18:30:55: MK5(0): DTR is up. >.Feb 25 18:30:55: Serial0: HDLC myseq 41, mineseen 0, yourseen 0, line down >.Feb 25 18:30:56: Serial0: attempting to restart >.Feb 25 18:30:56: MK5(0): Deasserting DSR >.Feb 25 18:30:56: MK5(0): Deasserting DSR >.Feb 25 18:30:56: MK5(0): Reset >.Feb 25 18:30:56: MK5(0): Asserting DSR >.Feb 25 18:30:56: MK5(0): Deasserting LTST >.Feb 25 18:30:56: MK5(0): Asserting DCD >.Feb 25 18:30:56: MK5(0): New serial state = 0x6017 >.Feb 25 18:30:56: MK5(0): DTR is up. >.Feb 25 18:31:00: MK5(0): New serial state = 0x603E >.Feb 25 18:31:00: MK5(0): DTR is down. >.Feb 25 18:31:00: MK5(0): New serial state = 0x6016 >.Feb 25 18:31:00: MK5(0): DTR is up. >.Feb 25 18:31:05: MK5(0): New serial state = 0x6016 >.Feb 25 18:31:05: MK5(0): DTR is up. >.Feb 25 18:31:05: Serial0: HDLC myseq 42, mineseen 0, yourseen 0, line down >R2# > >Thanks, > >Andy Fernandes ________________________ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=36442&t=36423 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
