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I have a Cisco 7206 router running IOS version 12.2(8)T10. When I enable the Fast Ethernet interface I see that the line protocol is down.
When I run the command show controllers I see the following :
#show controllers fastEthernet 0/0
Hardware is DEC21140A
link down, reason: MII link down
What are the reasons for having Line Protocol be Down, and what does "MII link down" error mean?
Any help would be greately appreciated.
Dmitry, few things.. the I/O type controler installed on that 7206 router has one builtin MII port and a RJ45 port for FE connection., are you using the RJ45 port for connecting it to a switch or the MII port using a transceiver.
line protocol down could be duplex missmatch, but from what I see in your show controllers is unclear as to what you are using to connect to a switch, or hub, or anything.
can you provide
" show ip interface brief "
I am using the RJ45 port to connect to another switch.
The interface was working for a long time but suddenly stopped and we had to disable it as the line protocol is down.
#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 A.B.C.D YES NVRAM up down
#sh int fastEthernet 0/0
FastEthernet0/0 is up, line protocol is down
Hardware is DEC21140A, address is 0002.1727.4000 (bia 0002.1727.4000)
Description: EGRESS to INTERNET
Internet address is A.B.C.D/28
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Fast-ethernet on C7200 I/O card with MII or RJ45 Port adapter, 1 port
Port adapter is analyzed
Port adapter insertion time 2y0w ago
EEPROM contents at hardware discovery:
Hardware revision 2.1 Board revision B0
Serial number 15783391 Part number 73-4092-03
FRU Part Number: C7200-IO-FE-MII/RJ45=
Test history 0x0 RMA number 00-00-00
EEPROM format version 1
EEPROM contents (hex):
0x20: 01 83 02 01 00 F0 D5 DF 49 0F FC 03 00 00 00 00
0x30: 58 00 00 00 00 03 05 00 00 00 FF FF FF FF FF FF
Can you revert on the other end device ? is this router connecting to a switch/firewall etc., if yes did u check the port status interface status both physically as well as with cli on the box ?
Do you have media type configured?
Have you checked cabling (i.e. connecting PC/Switch to the router directly to that port without all the infrastructure) ?
We had similar problem when our structured cable started malfunctioning.
Media type is not configured, it is default 100BaseX.
I even tried changing it to MII and then back to 100BaseX, still not working - line protocol stays Down.
Also testing the interface produced these results :
SBC-Outside-Primary-7206#test interfaces fastEthernet 0/0
... Failed - not connected problem
1 interfaces: 0 passed, 1 failed, 0 skipped, 0 untestable
We will try and change out the cable connecting the router to an Upstream switch, and check the port on that switch, to make sure that is not the problem.
Thank you for the suggestion. I suspect it is a cable issue.
I rebooted the router this morning and got the following message:
%DEC21140-5-NOCARR: FastEthernt 0/0 cable/connector problem?
I know that it refers to cable or transceiver failure. So I will investigate the cabling or try replacing the controller.
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