Category Archives: Switching

linkFlapErrDisabled error on cisco Nexus5500 Chassis

linkFlapErrDisabled error on cisco Nexus5500 Chassis

We observed linkFlapErrDisabled error on interface ethernet 2/7 on cisco Nexus5548 Chassis. We observed link flap on this interface 1week(s) 1day(s) ago.

Nexus5500# sh interface ethernet 2/7
Ethernet2/7 is down (linkFlapErrDisabled)
Dedicated Interface
Hardware: 1000/10000 Ethernet, address: 002a.6a18.ff86 (bia 002a.6a18.ff86)
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA
Port mode is trunk
auto-duplex, 10 Gb/s, media type is 10G
Beacon is turned off
Input flow-control is on, output flow-control is on
Rate mode is dedicated
Switchport monitor is off
EtherType is 0x8100
Last link flapped 1week(s) 1day(s)
Last clearing of "show interface" counters never
32 interface resets
30 seconds input rate 0 bits/sec, 0 packets/sec
30 seconds output rate 0 bits/sec, 0 packets/sec
Load-Interval #2: 5 minute (300 seconds)

We did a shut and unshut on this port and we see interface 2/7 up.

Nexus5500# conf t
Enter configuration commands, one per line. End with CNTL/Z.
Nexus5500(config)# int ethernet 2/7
Nexus5500(config-if)# shu
Nexus5500(config-if)# no shut
Nexus5500(config-if)# end
Nexus5500# sh interface ethernet 2/7
Ethernet2/7 is up
Dedicated Interface
Hardware: 1000/10000 Ethernet, address: 002a.6a18.ff86 (bia 002a.6a18.ff86)
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA
Port mode is trunk
full-duplex, 10 Gb/s, media type is 10G
Beacon is turned off
Input flow-control is on, output flow-control is on
Rate mode is dedicated
Switchport monitor is off
EtherType is 0x8100
Last link flapped 00:00:04
Last clearing of "show interface" counters never
33 interface resets
30 seconds input rate 0 bits/sec, 0 packets/sec
30 seconds output rate 0 bits/sec, 0 packets/sec
Load-Interval #2: 5 minute (300 seconds)

Issues with logging into EX Virtual Chassis via SSH and HTTP

What needs to be checked if we encounter issues with SSH and HTTP in Juniper Ex?

SSH:

If you encounter issues with users not able to log into the switch using SSH, check the following:

  •     SSH is properly configured. root@EX# set system services ssh
  •     No firewall filters for TCP blocking SSH.  root@EX3# show firewall  
  •     Make sure the directory /var/empty exists.

SSH access in juniper ex

If the directory is not present, create it as shown below:

    %cd /var
    %mkdir empty

HTTP/HTTPS:

If you are not able to log in to the switch using HTTP/HTTPS, check the following.

  •     HTTP is properly configured under web management.

root@SW1# set system services web-management http   

  •     No firewall filters blocking http traffic.
  •     Clear the cache in the browser 

The directory structure for HTTP is as below:

/packages/mnt/jweb-ex-9.5R2.7/jail/var/etc