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891F to IE3000-4TC & GLC-FE-100LX -

Level 1
Level 1

I have a 891F router that was intended to connect via the SFP port to a IE3000-4TC. One pair of SFPs (GLC-FE-100LX) were purchased. Both appeared as compatible in the compatibility matrix. 


However on the 891F I have speed 100 hard set, unable to change or remove. I do get some logging results;

*Nov 15 12:28:53.727: %LINK-3-UPDOWN: Interface GigabitEthernet8, changed state to up
*Nov 15 12:28:54.727: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet8, changed state to up
*Nov 15 12:28:57.727: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet8, changed state to down
*Nov 15 12:28:58.727: %LINK-3-UPDOWN: Interface GigabitEthernet8, changed state to down

On the IE3000 I see nothing logged for this port. For this switch I have;

interface GigabitEthernet1/1
 switchport access vlan 2
 ip device tracking maximum 0
 media-type sfp
IE3000(config-if)#do sh int gig 1/1
GigabitEthernet1/1 is down, line protocol is down (notconnect)
  Hardware is Gigabit Ethernet, address is 081f.f358.2c81 (bia 081f.f358.2c81)
  MTU 1500 bytes, BW 10000 Kbit/sec, DLY 1000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive not set
  Auto-duplex, Auto-speed, link type is force-up, media type is 1000BaseLX SFP
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  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: fifo
  Output queue: 0/40 (size/max)
  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 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     0 packets output, 0 bytes, 0 underruns
     0 output errors, 0 collisions, 1 interface resets
     0 unknown protocol drops
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 pause output
     0 output buffer failures, 0 output buffers swapped out

So, are one of the SFPs incompatible? Why does the IE3000 interface say 1000BaseLX? Is this the problem, the IE3000 trying connect at gig speeds where as the 891F is set to 100? I really thought this would be a simple matter of setting port to sfp media, and maybe setting speed (which I can not seem to change anyways)


For the 891F;

interface GigabitEthernet8
 ip address dhcp
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip flow ingress
 ip nat outside
 ip inspect DEFAULT100 out
 ip virtual-reassembly in
 duplex full
 speed 100
 media-type sfp
1 Reply 1

Reza Sharifi
Hall of Fame
Hall of Fame

GLC-FE-100LX is 100Mb optic. so,  I am not sure why the IE3000 showing it as Gig 

(media type is 1000BaseLX SFP)

.Can you hard set the switch side to 100Mb as well?  If that does not work, can you unplug the optic from the switch and and run the same command and see if the the output above disappears?


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