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Modifying queue depth and timeouts
11 Dell EMC SC Series: Best Practices with VMware vSphere | 2060-M-BP-V
Caution: Before running the following commands, refer to the latest documentation from VMware for the
latest information.
4.2.1 Fibre Channel HBAs
For each of these adapters, the method to set the driver queue depth and timeouts uses the following general
steps:
1. Locate the appropriate driver name for the module that is loaded:
- For QLogic, enter:
esxcli system module list |grep ql
- For Emulex, enter:
esxcli system module list |grep lpfc
Depending on the HBA model, the output could be similar to the following:
- QLogic: qla2xxx or qlnativefc
- Emulex: lpfc820
Note: The following steps contain example module names. The actual module names should be acquired
when completing step 1.
2. Set the driver queue depth and timeouts using the esxcli command:
- For QLogic, enter:
esxcli system module parameters set -m qlnativefc -p "ql2xmaxqdepth=255
ql2xloginretrycount=60 qlport_down_retry=60"
- For Emulex, enter:
esxcli system module parameters set -m lpfc820 -p "lpfc_devloss_tmo=60
lpfc_lun_queue_depth=254"
Note: In certain multipathing configurations, the qlport_down_retry value may be set lower to decrease
failover times between paths if one of the paths fails.
3. Reboot the ESXi host for these changes to take effect.
4. To verify the settings, use the following command:
esxcli system module parameters list -m=module(i.e. -m=qla2xxx)