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Can't pass traffic between Cisco 2821 and Dell PowerConnect 5548p via SFP.

Dimarc67 used Ask the Experts™
  • Cisco 2821 router with HWIC SFP port, hard-set to 1gb (unconfigurable).
  • Dell PowerConnect 5548p switch with 10gb SFP port, manually hard-set down to 1gb.
  • SFP copper-direct cable.  

According to documentation, the Cisco HWIC port supports only 1gb, so opposite port must be hard-set same.

Both ports show link lights, and status says they're UP, but no traffic is passed.  Tested more than one cable, and tested more than one port on the Dell switch.  Cisco router has no other SFP port for testing.

This seems like it should be a very simple network connection.  Anyone have any insights on this?

Config settings and status info is below.  

Cisco 2821 port config:
interface GigabitEthernet0/0/0
 ip address
 no negotiation auto

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Dell PowerConnect 5548p port config:
interface tengigabitethernet1/0/1
 speed 1000

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Cisco 2821 "sho int gi0/0/0":
router#sho int gi0/0/0
GigabitEthernet0/0/0 is up, line protocol is up
 Hardware is PM-3387, address is 001d.a188.c1eb (bia 001d.a188.c1eb)
 Internet address is
 MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
    reliability 128/255, txload 1/255, rxload 1/255
 Encapsulation ARPA, loopback not set
 Keepalive set (10 sec)
 Full-duplex, 1000Mb/s, link type is force-up, media type is
 output flow-control is XON, input flow-control is XON
 ARP type: ARPA, ARP Timeout 04:00:00
 Last input 00:11:27, output 00:00:01, 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 runts, 0 giants, 0 throttles
    1178 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
    0 watchdog, 0 multicast, 0 pause input
    0 input packets with dribble condition detected
    387 packets output, 29701 bytes, 0 underruns
    0 output errors, 0 collisions, 4 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

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Dell PowerConnect 5548p "sho int switchport te 1/0/1":
Name: te1/0/1
Switchport: enable
Administrative Mode: access
Operational Mode: up
Access Mode VLAN: 2
Access Multicast TV VLAN: none
Trunking Native Mode VLAN: 2
Trunking VLANs Enabled: 2
General PVID: 2
General VLANs Enabled: 2
General Egress Tagged VLANs Enabled: none
General Forbidden VLANs: none
General Ingress Filtering: enabled
General Acceptable Frame Type: all
General GVRP status: disabled
Customer Mode VLAN: none
Private-vlan promiscuous-association primary VLAN: none
Private-vlan promiscuous-association Secondary VLANs Enabled: none
Private-vlan host-association primary VLAN: none
Private-vlan host-association Secondary VLAN Enabled: none
DVA: disable

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SFP copper-direct cable
I guess it could be that DAC is not compatible at least with one of devices (if not both). Try with compatible SFPs + copper cable (if you have those) instead of DAC.
Could not get a working connection trying multiple SFP ports, adapters, and cables.  The only common item was the HWIC itself, and no spare to test against.

Just discovered the Cisco 2921 router (3 built-in gigibit ports) is cheaper to buy used than another HWIC (also used), so we'll simply replace the 2821 router to side-step the issue.
Encountered the same "issue" with the Cisco 2921 router. Further research made me realize I'd completely ignored required NAT'ing for WAN connection.  Once NAT'ing was enabled and configured on the WAN interface, traffic routing performed exactly as intended.  (Considering near negligible cost, still happy we upgraded the router.)