Juniper MX Upgrades Causing Overheating
Juniper changed the way they do temperature management on MX240 and MX480 chassis devices, somewhere between 15.1 and 17.3. The net result is that your chassis might run hotter after you upgrade, which can lead to the system shutting down some optics. Probably not what you want. Luckily there’s a few hidden commands you can use to change this behavior
“Optics will be disabled…”
Post upgrade, you might see higher temperatures reported by show chassis fpc. This system was reporting temperatures in the low 30s, now it reports 50:
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lindsayh@MX240> show chassis fpc
Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%)
Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Buffer
0 Empty
1 Online 50 22 1 22 22 22 2048 38 21
2 Empty
{master}
lindsayh@MX240>
On its own, that’s OK, until you start seeing log messages like this:
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FPC 1 temperature over 50 degrees C; non-high-temperature tolerant optics will be disabled in 58 seconds if condition persists
Yeah that’s not good, especially when it carries out the threat, and Continue reading
