Description

This article describes when the 'Mix of FAN TRAYS' alarms are generated on MX240/480/960 devices and how to clear the alarm. 

Solution

MX960 Cooling System Components:

  • Upper front fan tray
  • Lower front fan tray
  • Front air filter 


MX240/MX480 Cooling System Components:

  • Fan tray
  • Air filter


The 'MIX of Fan tray' alarm is generated when both regular fan tray and enhanced fan tray are installed on the chassis.

user@MX960-PE0> show chassis alarms no-forwarding
 
2 alarms currently active
Alarm time               Class  Description
2019-09-06 16:52:54 CST  Minor  Loss of communication with Backup RE
2019-09-06 16:52:54 CST  Minor  Mix of FAN TRAYS
 
user@MX960-PE0> show chassis hardware detail | match fan
Fan Tray 0       REV 05   740-014971   VT2644            Fan Tray
Fan Tray 1       REV 08   740-031521   ACDA6122          Enhanced Fan Tray
 
user@MX960-PE0> show log chassisd | no-more   
Sep  6 16:52:53  fm_hsl2_add_plane_staggered plane=5
Sep  6 16:52:53  FM: No PFE boards to send Tx train messages to. Ending event
Sep  6 16:52:53  FM: Completing Plane online fabric event for slot 5
Sep  6 16:52:53  FM: Plane Sate: 1 1 1 1  2 2 0 0; staggered_pmask: 15 2a 00 00  00 00 00 00
Sep  6 16:52:53  FM: Mux active/trained: 0/0 0/0 0/0 0/0  0/0 0/0 0/0 0/0; Mode:0 act_mask:0f
Sep  6 16:52:53  FM: End of Plane online fabric event for slot 5, evq=0x0
Sep  6 16:52:53  send: yellow alarm clear, device CB 2, reason CB 2 Fabric Chip 1 Not Online
Sep  6 16:52:53  pipe_write failure for alarmd; connection error: Broken pipe (errno 32)
Sep  6 16:52:53 CHASSISD_SNMP_TRAP7: SNMP trap generated: fabric plane online (jnxFruContentsIndex 12, jnxFruL1Index 3, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName CB 2, jnxFruType 5, jnxFruSlot 2)
Sep  6 16:52:53  FR: End of Plane online event for slot 5.
Sep  6 16:52:53  FR: No more events to process
Sep  6 16:52:53 CHASSISD_SIGPIPE: SIGPIPE received
Sep  6 16:52:53  fru power sequencer FPC 3 step 40
Sep  6 16:52:53  ch_fru_power_sequencer FPC 3 step 40
Sep  6 16:52:53  i2cs_deassert_hard_reset: FPC#3 - ok(green) LED turned off
Sep  6 16:52:54  chassis_handle_peer_receive: closing connection: errno = 0
 
Sep  6 16:52:54  closing connection on fd 39
Sep  6 16:52:54  ch_gencfg_chassis_startup_time_handler: master_re: true, GENCFG_CHASSIS_STARTUP_TIME, minor_type: 7
Sep  6 16:52:54  ipc pipe 0x943ed80 created
Sep  6 16:52:54  ch_signal_proc: Sent signal 1 to tnp.sntpd, pid=2127
Sep  6 16:52:54  alarmd connection completed
Sep  6 16:52:54  send: clear all chassis class alarms
Sep  6 16:52:54  send: yellow alarm set, device Bottom Fan Tray 1, reason Mix of FAN TRAYS
Sep  6 16:52:54  send: yellow alarm set, device Routing Engine 1, reason Loss of communication with Backup RE
 
user@MX960-PE0> show log messages | no-more
Sep   6 16:52:52  MX960-PE0 kernel: tcp_auth_ok: Packet from 213.200.92.239:50363 unexpectedly has MD5 digest
Sep   6 16:52:53  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Cleared Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6)
Sep   6 16:52:53  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Detected Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6)
Sep   6 16:52:53  MX960-PE0 rpd[4142]: task_connect: addr 213.200.87.211+179: No route to host
Sep   6 16:52:53  MX960-PE0 rpd[4142]: BGP_CONNECT_FAILED: bgp_connect_start: connect 213.200.87.211 (Internal AS 3257): No route to host
Sep   6 16:52:53  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Cleared Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6)
Sep   6 16:52:53  MX960-PE0 kernel: nd6_dad_start: DAD didn't start as it is already in progress 2001:668:0:2:ffff:0:5995:837e
Sep   6 16:52:53  MX960-PE0 kernel: nd6_dad_start: DAD didn't start as it is already in progress fe80::52c5:8dff:fed8:e906
Sep   6 16:52:53  MX960-PE0 rpd[4142]: KRT Ifstate: Received IPv6 address 2001:668:0:2:ffff:0:5995:837e on ifl xe-0/0/6.0. Flag:2.
Sep   6 16:52:53  MX960-PE0 mib2d[4635]: SNMP_TRAP_LINK_UP: ifIndex 573, ifAdminStatus up(1), ifOperStatus up(1), ifName xe-0/0/6
Sep   6 16:52:53  MX960-PE0 mib2d[4635]: SNMP_TRAP_LINK_UP: ifIndex 658, ifAdminStatus up(1), ifOperStatus up(1), ifName xe-0/0/6.0
Sep   6 16:52:53  MX960-PE0 rpd[4142]: KRT Ifstate: Received IPv6 address fe80::52c5:8dff:fed8:e906 on ifl xe-0/0/6.0. Flag:2.
Sep   6 16:52:53  MX960-PE0 mib2d[4635]: SNMP_TRAP_LINK_DOWN: ifIndex 573, ifAdminStatus up(1), ifOperStatus down(2), ifName xe-0/0/6
Sep   6 16:52:54  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Detected Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6)
Sep   6 16:52:54  MX960-PE0 alarmd[4629]: Alarm set: Fan color=YELLOW, class=CHASSIS, reason=Mix of FAN TRAYS
Sep   6 16:52:54  MX960-PE0 craftd[4138]:  Minor alarm set, Mix of FAN TRAYS
Sep   6 16:52:54  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Cleared Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6)
Sep   6 16:52:54  MX960-PE0 kernel: tcp_auth_ok: Packet from 213.200.92.221:51342 unexpectedly has MD5 digest
Sep   6 16:52:54  MX960-PE0 fpc0 XMCHIP(0): XMCHIP(0): XXLCE0: Port Alarms: Detected Ethernet MAC Remote Fault Delta Event for Port 5 (xe-0/0/6) 

A fan tray contains multiple fans that work in unison to cool the router components. If one fan fails, the host subsystem adjusts the speed of the remaining fans to maintain proper cooling. A red alarm is triggered when a fan fails, and a yellow alarm and red alarm is triggered when a fan tray is removed.

Enhanced Fan Trays are High capacity Fan trays which are required for the MPC and DPCE cards. The MX Series high-capacity fan trays satisfy cooling requirements for high-density DPCs and MPCs, and must be upgraded for proper cooling.

user@MX960-PE0> show chassis hardware detail | match fpc
FPC 1            REV 31   750-021566   CAFV7049          DPCE 4x 10GE R
FPC 2            REV 30   750-022765   CAAA5571          DPCE 20x 1GE + 2x 10GE
FPC 3            REV 08   750-063744   CALW9644          MPCE Type 2 3D
FPC 4            REV 09   750-063736   CAMH1383          MPCE Type 3 3D

High Capacity Fan trays are mandatory for MPCs and high capacity power supplies. 

High capacity PEMs can be identified as:

  • MX960 - PWR-MX960-4100-AC, PWR-MX960-4100-DC
  • MX240/MX480 – PWR-MX480-2520-AC; PWR-MX480-2520-DC
 
High capacity fan tray:
  • MX960   -   FFANTRAY-MX960-HC-S
  • MX480  - FFANTRAY-MX480-HC-S
  • MX240 - FFANTRAY-MX240-HC-S


Regular fan tray:

  • MX960  - FFANTRAY-MX960-S
  • MX480  - FFANTRAY-MX480-S
  • MX240 - FFANTRAY-MX240-S
  
High capacity fan trays are supported for the Junos OS Release 10.0 R1 or higher. High capacity fan trays on MX960 contains 12 fans, MX480 contains 6 fans and MX240 contains 3 fans.

To prevent overheating, install the replacement fan tray immediately after removing the existing fan tray.

To clear the alarm, it is recommended to upgrade both Fan Tray to an enhanced fan tray.