DBA commands for Azure Managed Instance for Apache Cassandra

Azure Managed Instance for Apache Cassandra is a fully managed service for pure open-source Apache Cassandra clusters. The service also allows configurations to be overridden, depending on the specific needs of each workload. This feature allows maximum flexibility and control where needed. This article describes how to run database administrator (DBA) commands manually when necessary.

DBA command support

With Azure Managed Instance for Apache Cassandra, you can run nodetool and sstable commands by using the Azure CLI for routine DBA administration. Not all commands are supported, and there are some limitations. For supported commands, see the following sections.

Run a nodetool command

Azure Managed Instance for Apache Cassandra provides the following Azure CLI command to run DBA commands:

az managed-cassandra cluster invoke-command --resource-group <rg> \
  --cluster-name <cluster> --host <ip of data node> --command-name nodetool \
  --arguments "<nodetool-subcommand>"="" "paramerter1"="" 

The subcommand needs to be in the --arguments section with an empty value. The nodetool flags without a value are in the form <flag>"=". If the flag has a value, it's in the form <flag>"="value.

This example shows how to run a nodetool command without flags. In this case, it's the nodetool status command:

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name nodetool --arguments "status"="" 

This example shows how to run a nodetool command with a flag. In this case, it's the nodetool compact command:

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name nodetool --arguments "compact"="" "-st"="65678794" 

Both return JSON in the following form:

{
    "commandErrorOutput": "",
    "commandOutput": "<result>",
    "exitCode": 0
}

In most cases, you need only commandOutput or exitCode. This example shows how to get only commandOutput:

az managed-cassandra cluster invoke-command --query "commandOutput" --resource-group $resourceGroupName \
  --cluster-name $clusterName --host $host --command-name nodetool --arguments getstreamthroughput=""

Run an sstable command

The sstable commands require read/write access to the Cassandra data directory and the Cassandra database to be stopped. To accommodate this requirement, specify these two parameters: --cassandra-stop-start true and --readwrite true.

az managed-cassandra cluster invoke-command --resource-group <test-rg> \
  --cluster-name <test-cluster> --host <ip> --cassandra-stop-start true --readwrite true \
  --command-name sstableutil --arguments "system"="peers"

{
"commandErrorOutput": "",
"commandOutput": "Listing files...\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-CompressionInfo.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Data.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Digest.crc32\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Filter.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Index.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Statistics.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-Summary.db\n/var/lib/cassandra/data/system/peers-37f71aca7dc2383ba70672528af04d4f/me-1-big-TOC.txt\n",
"exitCode": 0
}

Run other commands

The cassandra-reset-password command lets a user change their password for Cassandra.

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name cassandra-reset-password --arguments password="<password>"

The password is URL encoded (UTF-8) in this command, which means that the following rules apply:

• The alphanumeric characters a through z, A through Z, and 0 through 9 remain the same.
• The special characters ., -, *, and _ remain the same.
• The space character is converted into a plus sign (+).
• All other characters are unsafe and are first converted into one or more bytes by using some encoding scheme. The three-character string %xy represents each byte, where xy is the two-digit hexadecimal representation of the byte.

The cassandra-reset-auth-replication command lets a user change their schema for the Cassandra user. Separate the datacenter names by space.

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name cassandra-reset-auth-replication \
  --arguments password="<datacenters>"

The datacenters are URL encoded (UTF-8) when they're passed into this command, which means that the following rules apply:

• The alphanumeric characters a through z, A through Z, and 0 through 9 remain the same.
• The special characters ., -, *, and _ remain the same.
• The space character is converted into a plus sign (+).
• All other characters are unsafe and are first converted into one or more bytes by using some encoding scheme. The three-character string %xy represents each byte, where xy is the two-digit hexadecimal representation of the byte.

The sstable-tree command lets a user see their SSTables.

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name sstable-tree

The sstable-delete command lets a user delete their SSTables that were made before a certain time.

az managed-cassandra cluster invoke-command --resource-group <rg> --cluster-name <cluster> \
  --host <ip of data node> --command-name sstable-delete --arguments datetime="<YYYY-MM-DD hh:mm:ss>"

The datetime argument must be formatted as shown in the example. You can also add --dry-run="" as an argument to see which files the command deletes.

List of supported sstable commands

For more information on each command, see SSTable tools.

• sstableverify
• sstablescrub
• sstablemetadata
• sstablelevelreset
• sstableutil
• sstablesplit
• sstablerepairedset
• sstableofflinerelevel
• sstableexpiredblockers

List of supported nodetool commands

For more information on each command, see Use nodetool.

• status
• cleanup
• clearsnapshot
• compact
• compactionhistory
• compactionstats
• describecluster
• describering
• disableautocompaction
• disablehandoff
• disablehintsfordc
• drain
• enableautocompaction
• enablehandoff
• enablehintsfordc
• failuredetector
• flush
• garbagecollect
• gcstats
• getcompactionthreshold
• getcompactionthroughput
• getconcurrentcompactors
• getendpoints
• getinterdcstreamthroughput
• getlogginglevels
• getsstables
• getstreamthroughput
• gettimeout
• gettraceprobability
• gossipinfo
• info
• invalidatecountercache
• invalidatekeycache
• invalidaterowcache
• listsnapshots
• netstats
• pausehandoff
• proxyhistograms
• rangekeysample
• rebuild
• rebuild_index: For arguments, use "keyspace"="table indexname...".
• refresh
• refreshsizeestimates
• reloadlocalschema
• replaybatchlog
• resetlocalschema
• resumehandoff
• ring
• scrub
• setcachecapacity: For arguments, use "key-cache-capacity" = "<row-cache-capacity> <counter-cache-capacity>".
• setcachekeystosave: For arguments, use "key-cache-keys-to-save":"<row-cache-keys-to-save> <counter-cache-keys-to-save>".
• setcompactionthreshold: For arguments, use "<keyspace>"="<table> <minthreshold> <maxthreshold>.
• setcompactionthroughput
• setconcurrentcompactors
• sethintedhandoffthrottlekb
• setinterdcstreamthroughput
• setstreamthroughput
• settimeout
• settraceprobability
• statusbackup
• statusbinary
• statusgossip
• statushandoff
• stop
• tablehistograms
• tablestats
• toppartitions
• tpstats
• truncatehints
• verify
• version
• viewbuildstatus

Related content

• Create a managed instance cluster from the Azure portal
• Manage Azure Managed Instance for Apache Cassandra resources by using the Azure CLI
• Management operations in Azure Managed Instance for Apache Cassandra