If you want to deploy Db2® Warehouse in an MPP
environment, you must set up a POSIX-compliant cluster file system such as IBM Spectrum Scale and a storage device for that
file system. You can use IBM Cloud block storage, which
is iSCSI based, to set up the storage device.
Before you begin
Authorize the server to use an IBM Cloud storage device.
About this task
The following instructions apply to CentOS and RedHat operating systems.
Instructions for other operating systems might be different.
Procedure
-
Issue the following command:
-
Install the necessary packages by issuing the following command:
yum -y install iscsi-initiator-utils device-mapper-multipath.x86_64
-
Issue the following command:
-
Set up the multipath.conf file.
An example
follows:
# setup multipath.conf
cat <<EOF >> /etc/multipath.conf
defaults {
user_friendly_names no
max_fds max
flush_on_last_del yes
queue_without_daemon no
dev_loss_tmo infinity
fast_io_fail_tmo 5
}
blacklist {
wwid "SAdaptec*"
devnode "^hd[a-z]"
devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
devnode "^cciss.*"
}
devices {
device {
vendor "NETAPP"
product "LUN"
path_grouping_policy group_by_prio
features "3 queue_if_no_path pg_init_retries 50"
prio "alua"
path_checker tur
failback immediate
path_selector "round-robin 0"
hardware_handler "1 alua"
rr_weight uniform
rr_min_io 128
getuid_callout "/lib/udev/scsi_id -g -u -d /dev/%n"
}
EOF
-
Start the multipathd daemon by issuing the following commands:
modprobe dm-multipath
service multipathd start
chkconfig multipathd on
-
Verify the multipath configuration by issuing the following command:
-
On each node, configure iSCSI by specifying the following commands and information:
cp /etc/iscsi/iscsid.conf /etc/iscsi/iscsid.conf.backup cat <<EOF >> /etc/iscsi/iscsid.conf
node.session.auth.authmethod = CHAP
node.session.auth.username = iSCSI_username
node.session.auth.password = iSCSI_password
discovery.sendtargets.auth.authmethod = CHAP
discovery.sendtargets.auth.username = iSCSI_username
discovery.sendtargets.auth.password = iSCSI_password
EOF
cp /etc/iscsi/initiatorname.iscsi /etc/iscsi/initiatorname.iscsi.backup
rm -f /etc/iscsi/initiatorname.iscsi
cat <<EOF >> /etc/iscsi/initiatorname.iscsi
InitiatorName=IQN
EOF
-
Discover the iSCSI target by issuing the following command:
iscsiadm -m discovery -t sendtargets -p target_IP_address
-
Automatically log in to the iSCSI:
iscsiadm -m node -L automatic
-
List the iSCSIs that are visible to the system by issuing the following commands:
iscsiadm -m session
multipath -l
-
Check whether the iSCSI storage is visible by issuing the following command:
fdisk -l | grep /dev/mapper/3
The output of the command is a list of strings
that represent that iSCSIs, in the form
dev/mapper/string. You can use this string when you
set up IBM Spectrum Scale, which requires the
iSCSI device storage to be available but not mounted.
-
If you plan to deploy Db2 Warehouse in an SMP
environment or want to load data from the iSCSI storage, issue the following command. Specify a
string value from the output of the previous step. If you plan to load data from
the mounted file system, use /mnt/clusterfs/scratch as the mount point.
Otherwise, use /mnt/clusterfs.
mount /dev/mapper/string mount_point