Ethernet Switching
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Ethernet Switching

EX-4200 switch port showing Half Duplex

a week ago

I was wondering if anyone else was showing the same output when checking interface status. After our most recent upgrade to 15.1R7.8 our interfaces have been showing (Speed: Auto, Duplex: Half-duplex) instead of (Speed: Auto, Duplex: Auto) as in other versions. The Link partner shows connected at Link mode: Full-duplex, Speed: 1000 Mbps. I'm not sure if it's causing problems, but as I look through the statistics I think it is. This port currently has 9591 drops. I just cleared the stats and will monitor. We're showing the same behavior across many other virtual chassis and stand alone chassis. If this is a duplicate forum post my apologies in advance.
 
 
 
> show interfaces ge-0/0/16 media
Physical interface: ge-0/0/16, Enabled, Physical link is Up
  Interface index: 340, SNMP ifIndex: 1229
  Description:  
  Link-level type: Ethernet, MTU: 1514, LAN-PHY mode, Speed: Auto, Duplex: Half-duplex, BPDU Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled,
  Remote fault: Online, Media type: Copper
  Device flags   : Present Running
  Interface flags: SNMP-Traps Internal: 0x0
  Link flags     : None
  CoS queues     : 8 supported, 8 maximum usable queues
  Current address: xx:xx:xx:xx:xx:xx, Hardware address: xx:xx:xx:xx:xx:xx
  Last flapped   : 2018-07-10 18:01:17 EDT (16:28:43 ago)
  Input rate     : 512 bps (1 pps)
  Output rate    : 2096 bps (3 pps)
  Active alarms  : None
  Active defects : None
  MAC statistics:
    Input bytes: 61117235598, Input packets: 104139384, Output bytes: 44274883406, Output packets: 116256253
  Autonegotiation information:
    Negotiation status: Complete
    Link partner:
        Link mode: Full-duplex, Flow control: Symmetric/Asymmetric, Remote fault: OK, Link partner Speed: 1000 Mbps
    Local resolution:
        Flow control: Symmetric, Remote fault: Link OK
  Interface transmit statistics: Disabled
 
   
   
> show configuration interfaces ge-0/0/16
unit 0 {
    family ethernet-switching {
        vlan {
            members WORKSTATIONS;
        }
    }
}
 
 
Model: ex4200-48t
Junos: 15.1R7.8

6 REPLIES
Ethernet Switching
Solution
Accepted by topic author LovingTheJunos
Thursday

Re: EX-4200 switch port showing Half Duplex

a week ago

Saw the same issue on the QFX/ACX platform and it was just a cosmetic incorrect showing in the interface but I don't see the ex listed in the PR.  This was fixed in Junos 17

 

https://prsearch.juniper.net/InfoCenter/index?page=prcontent&id=pr1286709

 

Steve Puluka BSEET - Juniper Ambassador
IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP)
http://puluka.com/home
Ethernet Switching

Re: EX-4200 switch port showing Half Duplex

a week ago

What is the actual link partner and how is it configured?  Looks like link partner may auto-neg speed only, which would cause EX4200 port set to auto to default to half-duplex.

Ethernet Switching

Re: EX-4200 switch port showing Half Duplex

Thursday

Thanks for the reply and the PR link. I think it's cosmetic in the EX case also. There hasn't been any collisions or drops in the 21 hours since the statistics were last cleared.

Ethernet Switching

Re: EX-4200 switch port showing Half Duplex

Thursday

rccpgm - It's a mix of servers and workstations all configured for Auto Speed / Auto Duplex.

Ethernet Switching

Re: EX-4200 switch port showing Half Duplex

Thursday

FYI, EX4200 can never run 17.x code.  EX4200 code support stops at 15.1R'x'.  @LovingTheJunos, if you plug a PC set for Auto into a port on the EX4200, what does the EX4200 show?  This could be a cosmetic bug in 15.1R7.  What code release were you running previously?

Ethernet Switching

Re: EX-4200 switch port showing Half Duplex

Thursday

@rccpgm Thanks for the FYI...prior to running 15.1R7 we were at  version 15.1R6.7. The command output in the original post was of a port with a PC set for Auto/Auto.