Apache Ambari BOF Meet Up @ Hadoop Summit 2013 Configs http://www.meetup.com/Apache-Ambari-User-Group/events/119184782/

1. © Hortonworks Inc. 2013
Ambari
Configuration API
June 25, 2013
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2. © Hortonworks Inc. 2013
Agenda
• Purpose
• Types
• Cluster
• Host Overrides
• Host Component / Actual
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3. © Hortonworks Inc. 2013
Purpose
• Provide ability to set any config parameter
• Values used to populate configuration files in
/etc/hadoop/conf (core-site, hdfs-site, etc)
• Mechanism to set and view configurations
• Insight into host configuration state
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4. © Hortonworks Inc. 2013
Types
• Two main types: global and site
• Global Configuration
–Values required by shell or puppet scripts
–Denoted using specially named global type
• Site-specific Configurations
–Used by Hadoop components for fine-tuning a cluster
–Named using standard Hadoop types (core-site, hdfs-site, mapred-site,
etc)
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5. © Hortonworks Inc. 2013
Cluster - Definition
• All configurations stored with cluster
GET /api/v1/clusters/c1/configurations?type=global&tag=version1
{
"type": "global",
"tag": "version1",
"properties": {
"a": "b",
"c": "d"
}
}
• Uniqueness defined by type/tag combinations
• Type is matched to Hadoop configuration names, but
is not restricted
• Tag can be any string
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6. © Hortonworks Inc. 2013
Cluster – Desired
• Only One Desired per type
GET /api/v1/clusters/c1
{
"Clusters": {
"cluster_id": 1,
"desired_configs": {
"global": {
"tag": "version1",
"user": "admin"
}, ...
}
}
}
• Auditing username and timestamp
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7. © Hortonworks Inc. 2013
Host Overrides – Desired
• Mechanism to set specific host-level overrides
• Only One Desired per type, like Cluster
GET /api/v1/clusters/c1/hosts/h1
{
"Hosts": {
"cluster_name": "c1",
"host_name": "h1",
"desired_configs": {
"global": {
"tag": "custom-mapred",
"user": "admin"
}, ...
}
}
}
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8. © Hortonworks Inc. 2013
Host Components – Actual
• Discreet information, per Host Component
• Structure similar to Cluster/Host desired
GET /api/v1/clusters/c1/hosts/h1/host_components/DATANODE
{
"HostRoles" : {
"cluster_name" : "c1",
"component_name" : "DATANODE",
"actual_configs" : {
"core-site" : {
"tag" : "version1"
},
"global" : {
"tag" : "version1”
}
}
}
}
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9. © Hortonworks Inc. 2013
Thank You
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