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nexus 5010 connecting to catalyst 3750

unreal400 asked
I am trying to get my Nexus 5010 switches to communicate with my stacked 3750 switches but cannot get anything to route between the two.      There are connected through fiber SFP's  ports 51 and 52 on the 3750 and  ports 1/7 1/8 on the Nexus.  Links show active and connected.   All ports are in trunk mode with all vlans allowed.

Trunks are set up links are active  but I get no communication.    Is there something specific I need to set up on my Nexus 5010 to have it be able to communicate.   Any ideas of what I need to do.

nexus-01(config-if)# int eth 1/7
nexus-01(config-if)# show int eth 1/7
Ethernet1/7 is up
  Hardware: 1000/10000 Ethernet, address: 0005.9b75.be0e (bia 0005.9b75.be0e)
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA
  Port mode is trunk
  full-duplex, 1000 Mb/s, media type is 10g
  Beacon is turned off
  Input flow-control is off, output flow-control is off
  Rate mode is dedicated
  Switchport monitor is off
  Last link flapped 1week(s) 1day(s)
  Last clearing of "show interface" counters 1w1d
  1 minute input rate 11864 bits/sec, 4 packets/sec
  1 minute output rate 496 bits/sec, 1 packets/sec
    24053965 input packets 1191220 unicast packets 19552121 multicast packets
    3310624 broadcast packets 754923 jumbo packets 0 storm suppression packets
    2986708384 bytes
    151686 output packets 150946 multicast packets
    730 broadcast packets 0 jumbo packets
    14207097 bytes
    0 input error 0 short frame 0 watchdog
    0 no buffer 0 runt 0 CRC 0 ecc
    0 overrun  0 underrun 0 ignored 0 bad etype drop
    0 bad proto drop 0 if down drop 0 input with dribble
    0 input discard
    0 output error 0 collision 0 deferred
    0 late collision 0 lost carrier 0 no carrier
    0 babble
    0 Rx pause 0 Tx pause
  1 interface resets

---------------------------from  the  3750

cisco-01>show int gi1/0/51
GigabitEthernet1/0/51 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is 0022.0ca6.9db3 (bia 0022.0ca6.9db3)
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive not set
  Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseSX SFP
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:06, 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 12000 bits/sec, 13 packets/sec
     18478260 packets input, 1955364982 bytes, 0 no buffer
     Received 18446568 broadcasts (0 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 18371211 multicast, 0 pause input
     0 input packets with dribble condition detected
     6003442 packets output, 1653651045 bytes, 0 underruns
     0 output errors, 0 collisions, 1 interface resets
     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
Watch Question

can you provide a sho run int <int> of both devices I'm concerned with negotiation make sure it set to "non-negotiate"

If you're not using etherchannel then you may need to disconnect one of the lines.  I'm not sure how the Nexus IOS handles a loop, may disable one or both ports.

Port 17 on the Nexus shows a media type of 10G, but the 3750 shows 1000BaseSX SFP.  Is there a 1G or 10G SPF in the Nexus?

Type a "cdp show neighbor" from both switches to verify it they can see each other.

If none of those thinges help, please post configs and logs.
There are only 2 portson the Nexus that allow 1 Gig uplinks  so I had to shift the SFP to a different port.