Author Archives: Randy

XenServer multipath configuration for LIO targets

XenServer multipath.conf with special support for LIO-based iSCSI targets to maximize multipath performance and ensures 100% stability. path_grouping_policy setting doesn’t seem to matter (between group_by_prio and multibus) in most basic setups. Invalid lines (as reported by XenServer 6.1) have also been removed. http://djlab.com/stuff/xs61/multipath.conf Specifically: device { vendor “LIO-ORG” product “*” path_grouping_policy group_by_prio path_checker tur getuid_callout […]

X9SCM / X9SCL Network Timeout

Supermicro X9SCM and X9SCL main boards will lose network connection after some heavy traffic, especially on RHEL/CentOS 6. Updating BIOS and driver will not always fix this: Oct 19 18:32:49 zeus kernel: ————[ cut here ]———— Oct 19 18:32:49 zeus kernel: WARNING: at net/sched/sch_generic.c:267 dev_watchdog+0x26d/0x280() (Not tainted) Oct 19 18:32:49 zeus kernel: Hardware name: X9SCL/X9SCM […]

Kickstart 4-disk RAID10 Recipe

Here’s a nice recipe for a RAID10 array comprised of 4x SSD disks. Tested to work on CentOS 6 (RHEL 6). Be sure to add the discard option in fstab for Trim support. zerombr yes bootloader –location=partition –driveorder=sda,sdb,sdc,sdd clearpart –all –initlabel –drives=sda,sdb,sdc,sdd part raid.100000 –size=250 –ondisk=sda part raid.100001 –size=250 –ondisk=sdb part raid.100002 –size=250 –ondisk=sdc part […]

Xen 4 and Libvirt From Source on CentOS 6

Install some prerequisites: yum groupinstall “Development Libraries” “Development Tools” yum install mercurial python-devel dev86 iasl ncurses-devel ncurses \ glib2-devel glib2 openssl-devel yajl-devel libuuid-devel libuuid \ pciutils-devel pciutils texinfo kernel-xen bridge-utils gnutls gnutls-devel \ libxml2 libxml2-devel libnl libnl-devel libxslt libxslt-devel pygtk2 xorg-x11-xauth \ xorg-x11-fonts* device-mapper* gnome-python2-gconf pygtk2-libglade dbus-x11 \ gtk-vnc-python netcf netcf-devel netcf-libs vte vte-devel Pull […]