Skip to content

Setting SCSI Timeout Values for FreeBSD VMs on VMware/NetApp

NetApp requires setting a timeout value of 190 seconds for all VMware data stores on their filers to handle “long fabric or storage-side I/O interruptions”; this is done as follows on FreeBSD:

# sysctl kern.cam.da.default_timeout=190

This can be set permanently in /etc/sysctl.conf:

kern.cam.da.default_timeout=190

Elsewhere, I have seen a recommendation for FreeBSD on ESX that kern.cam.da.retry_count be set to 120.

2 Comments

  1. Do this setting prevent FreeBSD from crashing when storage volumes are migrating from a controller to another on the SAN ?

    Posted on 05-Apr-11 at 1:30 am | Permalink
  2. admin

    @Milu – Yes, it does keep FreeBSD from crashing during a controller takeover, in my limited experience.

    Posted on 05-Apr-11 at 8:02 am | Permalink

Post a Comment

Your email is never published nor shared. Required fields are marked *
*
*