"No link detected" from ethtool and mii-tool

Solution In Progress - Updated -

Environment

  • Red Hat Enterprise Linux (RHEL)
  • bnx2 Network Interface Card (NIC)

Issue

  • mii-tool reports no link for ethX
[root@RGxxx CM0000000586359]# mii-tool
SIOCGMIIREG on eth0 failed: Input/output error
ethX: negotiated 100baseTx-FD, link ok
SIOCGMIIREG on eth1 failed: Input/output error
eth1: negotiated 100baseTx-FD, link ok
SIOCGMIIPHY on 'eth2' failed: Resource temporarily unavailable
SIOCGMIIPHY on 'eth3' failed: Resource temporarily unavailable
eth4: no link
  • ethtool reports Link detected no for eth4 and eth5
Settings for eth4:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Advertised auto-negotiation: Yes
        Speed: Unknown! (65535)
        Duplex: Unknown! (255)
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: d
        Link detected: no                 <================

Settings for eth5:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Advertised auto-negotiation: Yes
        Speed: Unknown! (65535)
        Duplex: Unknown! (255)
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: d
        Link detected: no           <=================
  • But ifconfig reports link up for eth4 and eth5
eth4      Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx  
          UP BROADCAST SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:193 Memory:da000000-da012800 

eth5      Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx  
          UP BROADCAST SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:51 Memory:dc000000-dc012800

Resolution

  • Connect the cables to the NICs from the switch.

Root Cause

  • No cables plugged in the NICs

Diagnostic Steps

  • Check the ip link. "UP" means the interface has been started, while "LOWER_UP" means the cable is plugged in and has physical link
$ cat RGxx.12345-470304/sos_commands/networking/ip_link 
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond1 qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
4: eth2: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
5: eth3: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
6: eth4: <NO-CARRIER,BROADCAST,MULTICAST,SLAVE,UP> mtu 1500 qdisc pfifo_fast master bond1 qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
7: eth5: <NO-CARRIER,BROADCAST,MULTICAST,SLAVE,UP> mtu 1500 qdisc pfifo_fast master bond0 qlen 1000
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
8: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue 
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
9: bond1: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue 
    link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff

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