08-17-2009 09:02 AM - edited 03-04-2019 05:46 AM
Hi there Experts just badly needed a wonderful help for my Home Lab issue as I'm about to give up. Couldn't get the two interfaces pingable. I have got R1 and R2 connected via DCE/DTE cross-over serial cable and have configs for both routers shown below:
R1#sh run
Building configuration...
Current configuration : 811 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname R1
!
boot bootstrap tftp c2500-i-l.121-27b_4.bin 255.255.255.255
enable secret 5 $1$mdza$1Tcbw2xIy1KQ8XQy1mcHk0
enable password 7 05000F0433
!
ip subnet-zero
no ip domain-lookup
!
interface Ethernet0
ip address 192.168.1.1 255.255.255.0
!
interface Serial0
ip address 172.16.10.1 255.255.255.0
no keepalive
clockrate 64000
!
interface Serial1
ip address 172.16.11.1 255.255.255.0
no keepalive
clockrate 64000
!
interface BRI0
no ip address
no ip route-cache
no ip mroute-cache
shutdown
!
ip classless
R1#
R1#sh ip int brief
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES NVRAM administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.1 YES NVRAM up up
Serial0 172.16.10.1 YES NVRAM up up
Serial1 172.16.11.1 YES NVRAM down down
R1#
R1#sh controllers s 0
HD unit 0, idb = 0x12797C, driver structure at 0x12DD08
buffer size 1524 HD unit 0, V.35 DCE cable, clockrate 64000
cpb = 0x2, eda = 0x4140, cda = 0x4000
RX ring with 16 entries at 0x4024000
00 bd_ptr=0x4000 pak=0x12F1F8 ds=0x4027FC4 status=80 pak_size=0
01 bd_ptr=0x4014 pak=0x12F44C ds=0x4028680 status=80 pak_size=0
02 bd_ptr=0x4028 pak=0x12F6A0 ds=0x4028D3C status=80 pak_size=0
03 bd_ptr=0x403C pak=0x12F8F4 ds=0x40293F8 status=80 pak_size=0
04 bd_ptr=0x4050 pak=0x12FB48 ds=0x4029AB4 status=80 pak_size=0
05 bd_ptr=0x4064 pak=0x12FD9C ds=0x402A170 status=80 pak_size=0
06 bd_ptr=0x4078 pak=0x12FFF0 ds=0x402A82C status=80 pak_size=0
07 bd_ptr=0x408C pak=0x130244 ds=0x402AEE8 status=80 pak_size=0
08 bd_ptr=0x40A0 pak=0x130498 ds=0x402B5A4 status=80 pak_size=0
09 bd_ptr=0x40B4 pak=0x1306EC ds=0x402BC60 status=80 pak_size=0
10 bd_ptr=0x40C8 pak=0x130940 ds=0x402C31C status=80 pak_size=0
11 bd_ptr=0x40DC pak=0x130B94 ds=0x402C9D8 status=80 pak_size=0
12 bd_ptr=0x40F0 pak=0x130DE8 ds=0x402D094 status=80 pak_size=0
13 bd_ptr=0x4104 pak=0x13103C ds=0x402D750 status=80 pak_size=0
14 bd_ptr=0x4118 pak=0x131290 ds=0x402DE0C status=80 pak_size=0
15 bd_ptr=0x412C pak=0x1314E4 ds=0x402E4C8 status=80 pak_size=0
16 bd_ptr=0x4140 pak=0x131738 ds=0x402EB84 status=80 pak_size=0
cpb = 0x2, eda = 0x4800, cda = 0x4800
TX ring with 1 entries at 0x4024800
00 bd_ptr=0x4800 pak=0x000000 ds=0x4047E98 status=80 pak_size=285
01 bd_ptr=0x4814 pak=0x000000 ds=0x4048C10 status=80 pak_size=285
0 missed datagrams, 0 overruns
0 bad datagram encapsulations, 0 memory errors
0 transmitter underruns
0 residual bit errors
run out of characters will post the next configs on the next reply
Solved! Go to Solution.
08-17-2009 10:12 AM
Personally, I think you have a cable or interface problem. Do you have another cable you can try?
John
08-17-2009 10:33 AM
I have a hard time believing that the interfaces are bad, and I would be more hard pressed to believe that it was a bad cable.
You could try to manually specify hdlc encapsulation under the interfaces on both routers. HDLC is the default without specifying, but it's a L2 protocol meaning that you should be able to connect the cable, see the Up/Up status without having an address on the interface as long as HDLC was communicating with the other end.
You could also try ppp encapsulation and see if they come up. (I've never done the ppp encapsulation on a DCE/DTE cable.)
HTH,
John
08-17-2009 09:06 AM
First thing that jumps out is that you have the "no keepalive" listed under your serial interfaces. This will show the interface as "Up/Up" even if there's not a cable connected. Try putting the keepalive back on the interface, and then look at your interface status.
HTH,
John
08-17-2009 09:14 AM
thanks for the reply john really appreciated but when I tried changing back to default setting of keepalive my protocol went down:
R1#ping 172.16.10.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.10.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R1(config)#int s0
R1(config-if)#keepalive 10
R1(config-if)#^Z
R1#wr
Building configuration...
[OK]
R1#sh ip int brief
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES NVRAM administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.1 YES NVRAM up up
Serial0 172.16.10.1 YES NVRAM up down
Serial1 172.16.11.1 YES NVRAM down down
R1#
08-17-2009 09:17 AM
here's the new config:
R1#sh run
Building configuration...
Current configuration : 797 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname R1
!
boot bootstrap tftp c2500-i-l.121-27b_4.bin 255.255.255.255
enable secret 5 $1$mdza$1Tcbw2xIy1KQ8XQy1mcHk0
enable password 7 05000F0433
!
!
!
!
!
ip subnet-zero
no ip domain-lookup
!
!
!
!
interface Ethernet0
ip address 192.168.1.1 255.255.255.0
!
interface Serial0
ip address 172.16.10.1 255.255.255.0
clockrate 64000
!
interface Serial1
ip address 172.16.11.1 255.255.255.0
no keepalive
clockrate 64000
!
interface BRI0
no ip address
no ip route-cache
no ip mroute-cache
shutdown
!
ip classless
no ip http server
!
!
line con 0
password 7 094A420C01
login
line aux 0
line vty 0 4
password 7 00021F031C50020D1D
login
!
end
R1#
08-17-2009 09:18 AM
Could you post R2 config ?
08-17-2009 09:23 AM
Router2 Config:
R2#sh run
Building configuration...
Current configuration : 784 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname R2
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$i3C0$BjvjJfuGppy/dhNIt/JKf1
enable password 7 01180F0F49
!
no aaa new-model
ip subnet-zero
!
!
!
!
!
interface Ethernet0
ip address 192.168.1.2 255.255.255.0
!
interface Serial0
ip address 172.16.10.2 255.255.255.0
!
interface Serial1
ip address 172.16.11.2 255.255.255.0
no keepalive
!
interface BRI0
no ip address
encapsulation hdlc
no ip route-cache
shutdown
!
no ip http server
ip classless
!
!
!
!
line con 0
password 7 14111E0E14
login
line aux 0
transport input all
line vty 0 4
password 7 094A420C010E1E1919
login
!
end
R2#
08-17-2009 09:17 AM
More than likely it's not recognizing the cable between the two devices. The no keepalive "hides" the problem. :)
Can you post "sh int s0" from both routers? I'm assuming that your S0 is also configured on the other router, and can you post the other routers config as well?
John
08-17-2009 09:25 AM
R1#
R1#
R1#
R1#sh int s0
Serial0 is up, line protocol is down
Hardware is HD64570
Internet address is 172.16.10.1/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output 00:00:03, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
110 packets output, 12414 bytes, 0 underruns
0 output errors, 0 collisions, 25 interface resets
0 output buffer failures, 0 output buffers swapped out
60 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
R1#
R2#
R2#
R2#sh int s0
Serial0 is up, line protocol is down
Hardware is HD64570
Internet address is 172.16.10.2/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
122 packets output, 11686 bytes, 0 underruns
0 output errors, 0 collisions, 30 interface resets
0 output buffer failures, 0 output buffers swapped out
50 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
R2#
08-17-2009 09:30 AM
yeah this is weird but when I put the no keepalive command the interfaces will show Up Up. lolz.. this is weird though.
Anyone expertz experienced this kind of drama before?
08-17-2009 09:33 AM
Hello Paul,
check cabling you may have connected the ports R1:ser0 to R2:ser1 and r1:ser1 to r2:ser0
this could explain why enabling keepalive on ser0s you see them going down because ser1s still have no keepalive on them
cable type should be correct :
DCD=up DSR=up DTR=up RTS=up CTS=up
Hope to help
Giuseppe
08-17-2009 09:43 AM
when I put all the keepalives back all of my serial interfaces went down:
R2#sh int s0
Serial0 is down, line protocol is down
Hardware is HD64570
Internet address is 172.16.10.2/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output 00:00:56, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
215 packets output, 13732 bytes, 0 underruns
0 output errors, 0 collisions, 63 interface resets
0 output buffer failures, 0 output buffers swapped out
113 carrier transitions
DCD=down DSR=down DTR=down RTS=down CTS=down
R2#sh int s1
Serial1 is down, line protocol is down
Hardware is HD64570
Internet address is 172.16.11.2/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/0/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=down RTS=down CTS=up
R2#sh ip int brief
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES NVRAM administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.2 YES NVRAM up up
Serial0 172.16.10.2 YES NVRAM down down
Serial1 172.16.11.2 YES NVRAM down down
R2#
08-17-2009 09:45 AM
R1#sh int s0
Serial0 is down, line protocol is down
Hardware is HD64570
Internet address is 172.16.10.1/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output 00:04:27, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
206 packets output, 14526 bytes, 0 underruns
0 output errors, 0 collisions, 65 interface resets
0 output buffer failures, 0 output buffers swapped out
125 carrier transitions
DCD=up DSR=up DTR=down RTS=down CTS=up
R1#sh int s1
Serial1 is down, line protocol is down
Hardware is HD64570
Internet address is 172.16.11.1/24
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/0/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=down DSR=down DTR=down RTS=down CTS=down
R1#sh ip int brief
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES NVRAM administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.1 YES NVRAM up up
Serial0 172.16.10.1 YES NVRAM down down
Serial1 172.16.11.1 YES NVRAM down down
R1#
08-17-2009 09:51 AM
No keepalives on the interface isn't causing your issue though. Have you tried moving the same cable to S1 interface to see if you exhibit the same issue? Giuseppe is correct in that maybe you have the cable crossed from S0 to S1 on the other router?
John
08-17-2009 10:00 AM
Hi John,
The cable connected only from R1 S0 to R2 S0 but I tried connecting from R1 S0 to R2 S1 and change R2 S1's Ip Address but still can't ping at all the status down down
08-17-2009 10:08 AM
And I tried put all the settings back from where it was like no keepalive, serial cable connected from r1s0 to r2s0, put all together back even the IP Address, sh ip int brief:
R2#sh ip int brief
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES NVRAM administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.2 YES NVRAM up up
Serial0 172.16.10.2 YES NVRAM up up
Serial1 172.16.11.2 YES manual down down
R2#ping 172.16.10.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.10.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R2#
Still no luck.. c",)
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