Solution to Dell PowerEdge server loud fan

dell_loud_fan.txt

Reddit post: https://www.reddit.com/r/homelab/comments/j3hh1r/poweredge_r730xd_fans_loud_wont_slow_down_help/

iDRAC Setting Fan Speed on Poweredge R730xd with IPMI (should work with others but cmds will vary with device names
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Reference: https://gist.github.com/mdpuma/8972079b7da52afef15cc039039ff818
1. Get your iDRAC on the LAN and config a username and password
2. In the iDRAC interface (access via web browser), enable IPMI in iDRAC Settings > Network > IPMI Settings
3. Download/install the Dell iDRAC tools for windows (in this case, filename was DellEMC-iDRACTools-Web-WINPE-9.4.0-3732_A00.exe)
4.  Open a cmd prompt  (iDRAC IP in this example is 192.168.16.2)
5. 	cd c:\program files\dell\sysmgt\iDRACTools\IPMI

# Note when you change fan settings, give it a few seconds to happen, it isn't quite instant
# get list of devices.  Also "lanplus" is a specification, not your local interface name, so leave it as lanplus.
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** sdr list

# get fan speeds, exhaust temp  (use dev names from above cmd)
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** sensor reading "Fan1 RPM" "Fan2 RPM" "Fan3 RPM" "Fan4 RPM" "Fan5 RPM" "Fan6 RPM" "Exhaust Temp"

# change fan speed control to manual
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** raw 0x30 0x30 0x01 0x00

# set fan speed to 30% of max (hint: 0x1e is hexadecimal for 30)
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** raw 0x30 0x30 0x02 0xff 0x1e

# set fan speed to 40% of max (hint: 0x28 is hexadecimal for 40)
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** raw 0x30 0x30 0x02 0xff 0x28

# change fan speed control to automatic (if you want to go back to letting it manage itself and be unbearably loud again)
ipmitool -I lanplus -H 192.168.16.2 -U sysadmin -P ******** raw 0x30 0x30 0x01 0x01