The db2cluster command
is used to perform management operations related to DB2® cluster
services.
The db2cluster command is functionally
similar to the interactive db2haicu tool, but it
contains a much wider array of options for administering in a DB2 pureScale® environment.
Authorization
The
options of the db2cluster command that you can
use depend on your authorization level. Some options can only be specified
by the DB2 cluster
services administrator,
others can only be specified if you are part of the SYSADM, SYSCTL,
or SYSMAINT group, and a smaller subset of commands can be run by
any user ID on the system. See the Command parameters section for information on the authorities
required for each option. In addition, there is a set of advanced troubleshooting options for the db2cluster command,
which should only be used under the guidance of service.
Command syntax
Standard options
>>-db2cluster--+- -cm--| cm action |---+-----------------------><
'- -cfs--| cfs action |-'
cm action
|--+- -set--+- -tiebreaker--+- -majority--------+--------------------+-+--|
| | '- -disk--disk-name-' | |
| '- -option--+-HostFailureDetectionTime-- -value--value-+-' |
| +-pprimary-- -value--value-----------------+ |
| '-autofailback-- -value--+-off-+-----------' |
| '-on--' |
+- -list--+- -tiebreaker---------------+----------------------------+
| +- -alert--------------------+ |
| +- -HostFailureDetectionTime-+ |
| +- -pprimary-----------------+ |
| +- -LocalHostVersion---------+ |
| +- -DomainCommittedVersion---+ |
| '- -autofailback-------------' |
+- -verify--+- -resources---+---------------------------------------+
| '- -maintenance-' |
+-+- -enter-- -maintenance--+-------+-+-----------------------------+
| | '- -all-' | |
| '- -exit-- -maintenance-------------' |
+- -commit----------------------------------------------------------+
'- -clear-- -alert--+---------------------+-------------------------'
+- -member--member-id-+
+- -cf--cf-id---------+
'- -host--host-name---'
cfs action
|--+- -create-- -filesystem--fs-name-- -disk--disk-list--+-------------------------+-+--|
| '- -mount--directory-name-' |
+- -add-- -filesystem--fs-name-- -disk--disk1...diskN-----------------------------+
+- -remove-- -filesystem--fs-name-- -disk--disk-name------------------------------+
+- -delete-- -filesystem--fs-name-------------------------------------------------+
+- -set--+- -tiebreaker--+- -majority--------+-------------------------+----------+
| | '- -disk--disk-name-' | |
| '- -option--option-- -value--value--+-----------------------+-' |
| '- -filesystem--fs-name-' |
+- -list--+- -tiebreaker-----------------------------------+----------------------+
| +- -filesystem--+------------------------------+-+ |
| | '-fs-name--+-----------------+-' | |
| | +- -configuration-+ | |
| | '- -disk----------' | |
| +- -LocalHostVersion-----------------------------+ |
| '- -DomainCommittedVersion-----------------------' |
+- -verify--+- -configuration--+-----------------------+-+------------------------+
| | '- -filesystem--fs-name-' | |
| '- -maintenance------------------------------' |
+-+- -mount-----+-- -filesystem--fs-name------------------------------------------+
| +- -rebalance-+ |
| '- -unmount---' |
+-+- -enter-+-- -maintenance--+-------+-------------------------------------------+
| '- -exit--' '- -all-' |
'- -commit------------------------------------------------------------------------'
Advanced options
(1)
>>-db2cluster--+- -cm--| cm action |---+-----------------------><
'- -cfs--| cfs action |-'
cm action
|--+- -create--+-+-----------------------+- -host--host-name------------------------------------------------+-+--|
| | '- -domain--domain-name-' | |
| +- -resources--------------------------------------------------------------------------------+ |
| '- -unhealthy_host_response-- -option--+-reboot_host----+-- -option-- -apply_to_current_host-' |
| '-offline_member-' |
+-+- -add----+--+- -host--host-name----------------+-------------------------------------------------------+
| '- -remove-' '- -database_mounts--database-name-' |
+- -delete--+- -domain--domain-name--+---------+---------------------------+-------------------------------+
| | '- -force-' | |
| +- -resources--------------------------------------------------+ |
| '- -unhealthy_host_response-- -option-- -apply_to_current_host-' |
+- -list--+- -domain-----------------------------------------+---------------------------------------------+
| +- -host--+-------------------------+--+---------+-+ |
| | '-host-name1...host-nameN-' '- -state-' | |
| +- -configuration----------------------------------+ |
| +- -tiebreaker-------------------------------------+ |
| +- -alert------------------------------------------+ |
| '- -pprimary---------------------------------------' |
+- -repair--+- -resources------------------------+---------------------------------------------------------+
| '- -domain--domain-name--+---------+-' |
| '- -force-' |
+- -start--+- -domain--domain-name-----------+-------------------------------------------------------------+
| +- -host--host-name1...host-nameN-+ |
| '- -automation--------------------' |
'- -stop--+- -host--host-name-----+--+---------+-----------------------------------------------------------'
+- -domain--domain-name-+ '- -force-'
'- -automation----------'
cfs action
|--+- -create--+-----------------------+-- -host--host-name-------+--|
| '- -domain--domain-name-' |
+- -add--+- -host--host-name-----------------------+-----------+
| '- -network_resiliency -+---------------+-' |
| '- -gpfsadapter-' |
+- -remove-- -host--host-name----------------------------------+
+- -delete--+- -domain--domain-name-------------------+--------+
| '- -network_resiliency -+---------------+-' |
| '- -gpfsadapter-' |
+- -repair-- -network_resiliency -+---------------+------------+
| '- -gpfsadapter-' |
+- -start--+-------------------------------------+-------------+
| +- -timeout--seconds------------------+ |
| +- -host--host-name1...host-nameN-----+ |
| +- -all-------------------------------+ |
| '- -trace--+------------------------+-' |
| '- -option--option-value-' |
+- -stop--+-------------------------------------+--------------+
| +- -host--host-name--+---------+------+ |
| | '- -force-' | |
| +- -all-------------------------------+ |
| '- -trace--+------------------------+-' |
| '- -option--option-value-' |
'- -list--+--------------------------------------------------+-'
+- -domain-----------------------------------------+
+- -host--+-------------------------+--+---------+-+
| '-host-name1...host-nameN-' '- -state-' |
'- -network_resiliency -+---------------+----------'
+- -gpfsadapter-+
'- -resources---'
Notes:
- These command options are only displayed in the command
line help if you include the -advanced option
as follows: db2cluster -cm -help -advanced or db2cluster
-cfs -help -advanced
Command parameters
- -cm
- Specifies a resource-based command or maintenance operation
- -set
- Specifies the tiebreaker device for the cluster manager, the host
failure detection time, or the preferred primary cluster caching facility.
- -tiebreaker
- Specifies the type of device to be used as the DB2 cluster
services tiebreaker.
This option is only available to the DB2 cluster
services administrator.
- -majority
- Specifies that the surviving group of hosts with the majority
has operational quorum.
- -disk disk-name
- Specifies a shared disk partition that determines which group
of hosts has operational quorum.
- -option
- HostFailureDetectionTime -value value
- Specifies
the length of time (a range of 1 to 60 seconds)
for detecting a host failure or network partition in the cluster.
This option is only available to the DB2 cluster
services administrator.
- pprimary -value value
- Specifies which cluster caching facility DB2 cluster
services will
attempt to start in the primary role. This option is only available
to a user in the SYSADM, SYSCTL or SYSMAINT group.
- autofailback -value
- Specifies whether automatic failback of a member to its home host
is immediate (enabled) or automatic failback is delayed (disabled)
until automatic failback is manually enabled by the administrator.
Initially, automatic failback is enabled by default. The change to
this parameter will become effective after the instance is restarted.
- off
- Specify the off parameter to disable immediate
automatic failback of the member to its home host when the home host
becomes available. This setting provides time to verify the health
of the restarted home host before reintegrating it into the cluster.
- on
- Specify the on parameter to enable immediate
automatic failback of the member to its home host when the home host
becomes available.
- -list
- Returns details about the following:
- -tiebreaker
- Lists the type of device being used as the DB2 cluster
services tiebreaker
- -alert
- Lists any alerts for cluster elements
- -HostFailureDetectionTime
- Lists how long it will take for DB2 cluster
services to
detect a host failure or network partition
- -LocalHostVersion
- Lists the version of IBM® Tivoli® System
Automation for Multiplatforms (SA MP) (or IBM General Parallel File System
( GPFS™))
which is currently installed on the host where this command is invoked.
- -DomainCommittedVersin
- Lists the version of SA MP (or GPFS)
which is currently committed in the domain where this command is invoked.
- -pprimary
- Lists which cluster caching facility DB2 cluster
services is
designated as the preferred primary. This option is only available
to a user in the SYSADM, SYSCTL or SYSMAINT group.
- -autofailback
- Lists automatic failback status.
- -verify
- -resources
- Verifies that the resource model for the instance is correct,
and that there are no inconsistencies in the resource model.
- -maintenance
- Ensures that the cluster manager is offline on the host so that
the binaries can be updated.
- -enter -maintenance
- Puts the host on which this command was issued into maintenance
mode. This option is only available to the DB2 cluster
services administrator. Internally,
this option issues an asynchronous command to stop the cluster manager
on the host. The command polls the state of the cluster manager to
determine when the stop operation is completed. On less responsive
systems, it can timeout and report an error while the cluster manager
is in the process of shutting down. You can only put individual hosts
into maintenance mode one at a time.
- -all
- Puts the entire cluster
domain into maintenance mode, stopping the cluster manager on all
hosts in the instance.
- -exit -maintenance
- Removes the host on which this command was issued
from maintenance mode, and puts the domain online if it is currently
offline. This option is only available to the DB2 cluster
services administrator.
- -commit
- Commits the updates made to DB2 cluster
services and
makes them available to the DB2 database
system. This option is only available to the DB2 cluster
services administrator.
- -clear -alert
- Clears current alerts on the specified cluster element. This option
is only available to a user in the SYSADM, SYSCTL, or SYSMAINT group.
- -member member-id
- -cf cf-id
- -host host-name
- -cfs
- Specifies a cluster-file-system-based command or a maintenance
operation
- -create
- Creates a shared file system according to the following options
- -filesystem fs-name
- Specifies the name of the shared file system being created
- -disk disk-list
- Specifies the storage paths for the shared file system
- -mount directory-name
- Specifies the mount point for the shared file system. If no mount
point is provided, the file system is created under a root file system
name of /db2fs.
- -add
- Adds additional disks to an existing shared file system cluster
- -filesystem fs-name
- Specifies the name of the shared file system to which the disks
are to be added
- -disk disk-list
- Specifies the disks to be added to the shared file system cluster
- -remove
- Removes disks from an existing file system cluster
- -filesystem fs-name
- Specifies the name of the shared file system from which the disks
are to be removed
- -disk disk-name
- Specifies the disks to be removed from the shared file system
cluster. The command will fail if the specified disk is the last disk
in the file system or if it is the tiebreaker disk.
- -delete
- Deletes a shared file system. This option is only available to
the DB2 cluster
services administrator.
- -filesystem fs-name
- Specifies the name of the shared file system that is to be deleted.
The command will fail if the file system is not empty.
- -set
- Specifies the tiebreaker type or sets configuration options. This
option is only available to the DB2 cluster
services administrator.
- -tiebreaker
- Specifies the type of device to be used as the GPFS tiebreaker:
- -majority
- Specifies that the surviving group of hosts with the majority
has operational quorum.
- -disk disk-name
- Specifies a shared disk partition that determines which group
of hosts has operational quorum.
- -option option
Explicitly sets a configuration option for the cluster file
system. In most cases, you do not need to set any of these values
because they are automatically set to optimal values when the cluster
is created. The cluster verification that runs implicitly after installation
and updates returns an error message if any of the options is not
set to its mandatory value.
- adminMode
- Specifies whether all nodes in the cluster, or just a subset of
the nodes, are to be used for issuing GPFS administration
commands. The default and mandatory value is allToAll.
- maxFilesToCache
- Specifies the number of inodes to cache for recently used files
that are closed. The default and minimum mandatory value is 10000.
- maxMBpS
- Specifies an estimate of how many megabytes of data can be transferred
per second into or out of a single node. The default value is 150.
Increase this value if more I/O is required.
- pagepool
- Specifies the size in megabytes of the cache on each node. The
default and minimum mandatory value is 512.
- sharedMemLimit (AIX only)
- Specifies the amount of memory, in megabytes, available to store
various GPFS structures.
The default and minimum mandatory value is 2047.
- totalPingTimeout
- Specifies the length of time in seconds that GPFS waits
before expelling nodes it cannot communicate with when the primary
subnet is not used for GPFS communication.
The default value is 45 in clusters that have use
SCSI-3 Persistent Reserve (PR) and 75 in clusters
that do not have PR enabled.
- usePersistentReserve
- Specifies whether to enable or disable PR on the disks. The default
value is YES. If you change the setting to NO,
then fast failure recovery is replaced with a longer GPFS lease timeout
wait period, resulting in a slower failure recovery. This feature
is not available on Linux operating systems and the lease timeout
is always used for file system recovery.
- verifyGpfsReady
- Specifies that the peer domain is to be coordinated with the GPFS cluster,
ensuring that the GPFS mounts
the file system at the appropriate time. The default and mandatory
value is YES.
- worker1Threads
- Specifies the maximum number of concurrent file operations. The
default value is 500.
- -value value
- Specifies a value for the option.
- -filesystem fs-name
- Specifies which file system the configuration option will be applied
to.
- -list
- Returns details about the following:
- -tiebreaker
- Lists the type of device being used as the GPFS tiebreaker.
- -filesystem fs-name
- Returns details about the following:
- -configuration
- Lists the current configuration of the file system and configuration
parameters that can be changed.
- -disk
- Lists the current disks in the file system.
- -LocalHostVersion
- Lists the version of SA MP (or GPFS)
which is currently installed on the host where this command is invoked.
- -DomainCommittedVersion
- Lists the version of SA MP (or GPFS)
which is currently committed in the domain where this command is invoked.
- -verify
- -configuration
Verifies the code version and the release level of the
GPFS cluster,
and checks certain configuration settings for the cluster file system,
including the following options:
If any of these options are not set to the recommended value
for optimal cluster file system performance, a warning message is
returned by the
db2cluster command informing you
that the relevant option is not optimally set.
- -maintenance
- Ensures the shared file system cluster host is offline to allow
for updates to the binaries.
- -mount -filesystem fs-name
- Makes the specified file system available to the operating system
for read and write access by users.
- -rebalance -filesystem fs-name
- Restripes the data on disk across all disks in the file system.
This option should be run during periods of lower system activity
for the file system being rebalanced.
- -unmount -filesystem fs-name
- Makes the specified file system inaccessible to the operating
system
- -enter -maintenance
- Puts the host on which this command was issued into maintenance
mode. This option is only available to the DB2 cluster
services administrator. The cfs action db2cluster -cfs -enter -maintenance command
requires that the host already be entered into CM maintenance state.
- -all
- Puts all hosts in the shared file system cluster into maintenance
mode.
- -exit -maintenance
- Removes the host on which this command was issued from maintenance
mode. This option is only available to the DB2 cluster
services administrator. The cfs action db2cluster -cfs -exit -maintenance command
requires that the host not be in CM maintenance state.
- -all
- Ensures all hosts in the shared file system cluster are started.
- -commit
- Commits the updates made to DB2 cluster
services and
makes them available to the DB2 database
system. This option is only available to the DB2 cluster
services administrator.
Advanced command parameters
- -cm
- -create
- Creates a peer domain or a resource model. This option is not
normally needed unless directed by service.
- -domain domain-name -host host-name
- Creates a peer domain. The host named in the command must be the
local host and must have the DB2 cluster
services software
already installed. Specify a domain name if you want to change the
name of the peer domain to something other than the default: db2domain.
This option is only available to the DB2 cluster
services administrator.
- -resources
- Creates the cluster manager resource model for the instance based
on the information in the db2nodes.cfg file.
This option is only available to a user in the SYSADM, SYSCTL, or
SYSMAINT group.
- -unhealthy_host_response -option
- Specifies that DB2 cluster
services is
to take one of the following actions if a host experiences excessive
load or paging that could impact throughput or availability in the
rest of the cluster. The criteria for this response are as follows:
PctTotalPgSpFree < 95% and VMPgInRate > 20 per second
where PctTotalPgSpFree is
the percentage of free page space (meaning that page file usage is
greater than 5%) and VMPgInRate is the page-in
rate.- -reboot_host
- Reboots the host. Any resident member on
the host will restart in light mode on a guest host until its home
host has successfully rebooted. If the primary cluster caching facility is
on the host, the secondary cluster caching facility will
take over as the new primary; after the old primary’s host has successfully
rebooted, it will rejoin the cluster as the secondary cluster caching facility.
- -offline_member
- Forces any member or cluster caching facility on
the host offline. An offlined cluster caching facility will
not restart until the resulting alert is manually cleared. An offlined member restarts
in light mode on a guest host and will not restart on its home host
until the resulting alert is manually cleared.
- -option -apply_to_current_host
- Specifies that the unhealthy host response is to be applied to
the current host.
Note: This option should be used with caution and
can only be run as the DB2 cluster
services administrator. For more information, see the "Related links" section.
- -add
- Adds either a host or database mounts to the cluster manager domain.
To add a host, you must run the command from an online host that is
already in the peer domain. This option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name
- Adds a host (one at a time) to the cluster manager domain. The
software must already be installed on the host that will be added
to the cluster and be ready for usage.
- -database_mounts database-name
- Adds mount resources for a database that was not created with
the instance that is being used. You would use this, for example,
if the database is migrated from version 9.7 or if the database was
created with another instance and then cataloged to be used with the
current instance.
- -remove
- Removes either a host or database mounts from the cluster manager
domain. To remove a host, you must run the command from an online
host that is in the peer domain. This option is only available to
the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name
- Removes a single host from the cluster manager domain. Any members or cluster
caching facilities must
have already been removed from the host.
- -database_mounts database-name
- Removes mount resources for a database.
- -delete
- Deletes either a peer domain or the resource model. This option
is not normally needed unless directed by service.
- -domain domain-name
- Deletes the peer domain. This option is only available to the DB2 cluster
services administrator.
- -force
- The force option can be used to force the instance domain resources
to be deleted, even if there are any online cluster resources on the
domain.
- -resources
- Deletes the cluster manager resource model. Once resources are
deleted, the DB2 instance cannot
start until the resource model is properly re-created. This option
is only available to a user in the SYSADM, SYSCTL, or SYSMAINT group.
- -unhealthy_host_response
- Deletes the automated response (either rebooting the host reboot
or taking any member or cluster caching facility on
the host offline) on hosts that experience excessive load or paging.
If this condition occurs, the instance takes no action and the condition
is logged by the member or cluster caching facility (the
default behavior).
- -list
- Returns information about these options:
- -domain
- Returns the name of the active cluster manager peer domain.
- -host host-name1...host-nameN
- Lists the hosts that are in the peer domain.
- -state
- Returns the state of the hosts that are in the peer domain.
- -repair
- Repairs an inconsistent resource model or domain for an instance.
The DB2 instance resources are
re-created based on the last good instance configuration; that is,
the instance configuration from which the db2start command
was last successful.
- -resources
- Specifies to repair the resource model of the instance.
- -domain domain-name
- Specifies to repair the cluster manager domain. The domain is
re-created using the same topology configuration as the existing cluster
manager domain. This includes the existing set of cluster hosts in
addition to initializing the DB2 cluster
services tiebreaker and host failure detection time. Currently only
one instance per cluster is supported, and this instance must be specified
by setting the DB2INSTANCE environment variable.
This command can only be run as the DB2 cluster
services administrator. For more information, see the "Related links" section.
- -force
- Forces the domain to be repaired even if there are online cluster
resource groups on the domain.
- -start
- Starts one of these options:
- -domain domain-name
- Starts the peer domain. The start can only start other nodes
if the domain is already started on the current host. This option
is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name1...host-nameN
- Specifies which hosts the peer domain is to be started on. This
option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -automation
- Brings the cluster manager out of high availability service mode.
This option is only available to the DB2 cluster
services administrator
and users in the SYSADM, SYSCTL, or SYSMAINT group. This option is
only to be used with the aid of service, so it is not accessible unless
the service password has been set.
- -stop
- Stops one of these options:
- -domain domain-name
- Stops the cluster manager across the entire peer domain. This
option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name1...host-nameN
- Stops the cluster manager on the specified hosts. This option
is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -automation
- Puts the cluster manager into high availability service mode.
This option is only available to the DB2 cluster
services administrator
and users in the SYSADM, SYSCTL, or SYSMAINT group. This option is
only to be used with the aid of service, so it is not accessible unless
the service password has been set.
- -force
- Forces
the shutdown of the specified domain or host without performing checks
such as ensuring that operational quorum is kept. For example, if
the -force option is used with the -domain option,
the entire cluster manager peer domain is shut down, whereas with
the -host option only the host is shut down.
- -cfs
- -create -domain domain-name -host host-name
- Creates a shared file system cluster. The host named in the command
must be the local host and must have the DB2 cluster
services software
already installed. Specify a domain name if you want to change the
name of the shared file system cluster to something other than the
default: db2gpfsdomain. This option is only available
to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -add
- Adds either a host or network resiliency to the shared file system
cluster. The command must be run from an online host that is already
in the peer domain. This option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name
- Adds a host (one at a time) to the shared file system cluster.
The software must already be installed on the host that will be added
to the cluster and be ready for usage.
- -network_resiliency
- Adds condition and response resources for the adapter used by
the cluster file system. When the adapter changes state (going offline
or online) the cluster manager invokes a response script which takes
appropriate action.
- -gpfsadapter
- Specifies that the GPFS adapter
should be operated on. It is not required because this is currently
the only network resiliency resource that can be operated upon.
- -remove -host host-name
- Removes a single host from shared file system cluster. Any members or cluster
caching facilities must
have already been removed from the host. This command must be run
from an online host that is in the shared file system cluster. This
option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -delete
- Deletes either the shared file system cluster or the network resiliency.
This option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -domain domain-name
- Deletes the shared file system cluster.
- -network_resiliency
- Deletes the condition and response resources for the adapter used
by the cluster file system.
- -gpfsadapter
- Specifies the GPFS adapter
for the network -network_resiliency that is being
deleted.
- -start
- This option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name1...host-nameN
- Starts the shared file system processes on the specified hosts.
- -all
- Starts the shared file system processes on all hosts.
- -trace
- Enables AIX® tracing of the GPFS component
- -stop
- This option is only available to the DB2 cluster
services administrator
and is not normally needed unless directed by service.
- -host host-name
- Stops the shared file system daemons on the specified host.
- -force
- Specifies that there is no check to ensure that operational quorum
is kept.
- -all
- Stops the shared file system daemons on all hosts.
- -trace
- Stops the AIX tracing of
the GPFS component.
- -list
- Returns information about these options:
- -domain
- Returns the name of the shared file system cluster.
- -host host-name1...host-nameN
- Lists the hosts that are in the shared file system cluster.
- -state
- Returns the state of the hosts that are in the shared file system
cluster.
- -network_resiliency
- Lists the names of the network resiliency condition and response
resources in the cluster.
- -gpfsadapter
- Lists the GPFS adapter
for the network -network_resiliency.
- -resources
- Lists the contents of the network resiliency condition and response
resources in the cluster.
Examples
- Example 1
To list the file systems, use the following
db2cluster command:
db2cluster -cfs -list -filesystem
- Example 2
To list any alerts for cluster elements, use the following
db2cluster command:
db2cluster -cm -list -alert
The
following is a sample output when you run the command:
Alert: DB2 member '0' failed to start on its home host 'HostA'. The cluster manager will
attempt to restart the DB2 member in restart light mode on another host. Check the
db2diag.log for messages concerning failures on host 'HostA' for member '0'."
Action: This alert must be cleared manually with the command: 'db2cluster -cm -clear -alert'.
Impact: DB2 member '%0' will not be able to service requests until this alert has been
cleared and the DB2 member returns to its home host.
Usage
notes
If the ALERT column has a YES entry after running
the command db2instance -list, the db2cluster
-cm -list -alert command can be used to find out more information
about corrective action.