On MX and PTX platforms with Next Generation Routing Engines (NG-RE: RE-MX-X6, RE-MX-X8, and RE-PTX-X8) installed, the CLI command 'show vmhost management-if' must be used to find the correct management port link speed and mode. This is because running 'show interfaces fxp0 ' on NG-RE always show 1000mbps speed and Full-duplex mode , regardless of the actual link speed and mode.
'show vmhost management-if'
'show interfaces fxp0 '
This article explains why the command, ' show interfaces fxp0' should not be used on MX and PTX platforms with NG-RE installed.
' show interfaces fxp0'
Test topology:
mx204 MGMT fxp0 --------- LAN UTP ---------- ge-1/2/0 mx80 fxp0 --- LAN UTP --- Local PC
COM -------------- Serial console -------------------------------------- COM
test@mx80> show chassis hardware
Hardware inventory: Item Version Part number Serial number Description Chassis E4244 MX80 Midplane REV 07 711-031594 YL2374 MX80 PEM 0 Rev 03 740-028288 UG00858 AC Power Entry Module PEM 1 Rev 04 740-028288 WF05473 AC Power Entry Module Routing Engine BUILTIN BUILTIN Routing Engine TFEB 0 BUILTIN BUILTIN Forwarding Engine Processor QXM 0 REV 05 711-028408 YM1313 MPC QXM FPC 0 BUILTIN BUILTIN MPC BUILTIN MIC 0 BUILTIN BUILTIN 4x 10GE XFP PIC 0 BUILTIN BUILTIN 4x 10GE XFP FPC 1 BUILTIN BUILTIN MPC BUILTIN MIC 1 REV 26 750-028392 ZN2537 3D 20x 1GE(LAN) SFP PIC 2 BUILTIN BUILTIN 10x 1GE(LAN) SFP Xcvr 0 REV 02 740-013111 I363002 SFP-T <-- This is connected to mx204 MGMT fxp0 PIC 3 BUILTIN BUILTIN 10x 1GE(LAN) SFP Fan Tray Fan Tray
Test 1
MX204 MGMT fxp0 is Up with 1G and Full-duplex by auto-negotiation.
When MX80 ge-1/2/0 is auto-negotiation configured, MGMT port fxp0 is Up with 1000mbps and Full-duplex. Both commands, 'show interfaces fxp0' and 'show vmhost management-if' show 1000mbps and Full-duplex.
'show interfaces fxp0'
test@mx80> show configuration interfaces ge-1/2/0
gigether-options { auto-negotiation; }
test@mx80> show interfaces ge-1/2/0 media
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 1000mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 16:11:48 JST (00:01:28 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 282, Input packets: 2, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 2, Padded packets: 0, Output packet errors: 0 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, Local link Speed: 1000 Mbps , Link mode: Full-duplex Interface transmit statistics: Disabled
lab@mx204> show configuration groups jnpr-poc interfaces fxp0
unit 0 { family inet { address 172.27.115.99/22; } }
lab@mx204> show interfaces fxp0 media
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 16:11:47 JST (00:03:49 ago) Input packets : 9847233 Output packets: 7750
lab@mx204> show vmhost management-if
Administrative status: Up Link status: Up Link speed: 1000Mb/s Link operational mode: Full
Test 2
MX204 MGMT fxp0 is Up with 1G and Full-duplex by no-auto-negotiation.
Note: Half-duplex mode with 1000mbps is not supported by any of the PHY chip vendors.
gigether-options { no-auto-negotiation; }
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 1000mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Disabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 17:15:01 JST (00:00:20 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 3588, Input packets: 41, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 40, Padded packets: 0, Output packet errors: 0 Autonegotiation information: Negotiation status: Complete Interface transmit statistics: Disabled
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 17:15:00 JST (00:02:49 ago) Input packets : 18976602 Output packets: 28435
Test 3
speed 100m; gigether-options { auto-negotiation; }
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 100mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 16:17:34 JST (00:00:12 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 1222, Input packets: 12, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 12, Padded packets: 0, Output packet errors: 0 Autonegotiation information: Negotiation status: Complete Link partner: Link mode: Full-duplex, Flow control: Symmetric/Asymmetric, Remote fault: OK, Link partner Speed: 100 Mbps Local resolution: Flow control: Symmetric, Remote fault: Link OK, Local link Speed: 1000 Mbps , Link mode: Full-duplex Interface transmit statistics: Disabled
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 16:17:35 JST (00:01:50 ago) Input packets : 9847233 Output packets: 7758
Administrative status: Up Link status: Up Link speed: 100Mb/s Link operational mode: Full
Test 4
MX204 MGMT fxp0 is Up with 100m and Half-duplex by no-auto-negotiation.
speed 100m; gigether-options { no-auto-negotiation; }
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 100mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Disabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 17:19:11 JST (00:00:17 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 3964, Input packets: 45, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 44, Padded packets: 0, Output packet errors: 0 Autonegotiation information: Negotiation status: Incomplete Interface transmit statistics: Disabled
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 17:19:09 JST (00:02:21 ago) Input packets : 18976602 Output packets: 28447
Administrative status: Up Link status: Up Link speed: 100Mb/s Link operational mode: Half
Test 5
MX204 MGMT fxp0 is Up with 10m and Full-duplex by auto-negotiation.
speed 10m; gigether-options { auto-negotiation; }
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 10mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 16:20:51 JST (00:00:28 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 2162, Input packets: 22, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 22, Padded packets: 0, Output packet errors: 0 Autonegotiation information: Negotiation status: Complete Link partner: Link mode: Full-duplex, Flow control: Symmetric/Asymmetric, Remote fault: OK, Link partner Speed: 10 Mbps Local resolution: Flow control: Symmetric, Remote fault: Link OK, Local link Speed: 1000 Mbps , Link mode: Full-duplex Interface transmit statistics: Disabled
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 16:20:51 JST (00:01:22 ago) Input packets : 9847233 Output packets: 7780
Administrative status: Up Link status: Up Link speed: 10Mb/s Link operational mode: Full
Test 6
MX204 MGMT fxp0 is Up with 10m and Half-duplex by no-auto-negotiation
speed 10m; gigether-options { no-auto-negotiation; }
Physical interface: ge-1/2/0, Enabled, Physical link is Up Interface index: 152, SNMP ifIndex: 521 Link-level type: Ethernet, MTU: 1514, MRU: 1522, LAN-PHY mode, Speed: 10mbps , BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Disabled, Remote fault: Online Pad to minimum frame size: Disabled Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 80:71:1f:c5:b1:78, Hardware address: 80:71:1f:c5:b1:78 Last flapped : 2020-11-06 17:22:46 JST (00:00:17 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None PCS statistics Seconds Bit errors 0 Errored blocks 0 Ethernet FEC statistics Errors FEC Corrected Errors 0 FEC Uncorrected Errors 0 FEC Corrected Errors Rate 0 FEC Uncorrected Errors Rate 0 MAC statistics: Input bytes: 5210, Input packets: 63, Output bytes: 0, Output packets: 0 Filter statistics: Filtered packets: 62, Padded packets: 0, Output packet errors: 0 Autonegotiation information: Negotiation status: Incomplete Interface transmit statistics: Disabled
Physical interface: fxp0, Enabled, Physical link is Up Interface index: 64, SNMP ifIndex: 1 Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps Device flags : Present Running Interface flags: SNMP-Traps Link type : Full-Duplex Current address: e4:fc:82:45:80:42, Hardware address: e4:fc:82:45:80:42 Last flapped : 2020-11-06 17:22:46 JST (00:01:02 ago) Input packets : 18976602 Output packets: 28459
Administrative status: Up Link status: Up Link speed: 10Mb/s Link operational mode: Half
On MX and PTX platforms with Next Generation Routing Engines (NG-RE : RE-MX-X6, RE-MX-X8, and RE-PTX-X8) installed, the command 'show vmhost management-if' must be used to find the correct MGMT port link speed and mode. This is because running the command 'show interfaces fxp0' on NG-RE always shows speed 1000mbps and mode Full-Duplex , regardless of the actual Link speed and mode. Do not use the command, 'show interfaces fxp0' on MX and PTX platforms with NG-RE installed.