discovery-patterns

Discovery Patterns for ServiceNow

Discovery automatically populates the CMDB by scanning networks and systems.

Discovery Architecture

Discovery Schedule
    ↓
MID Server
    ↓
Probes (collect data)
    ↓
Sensors (process data)
    ↓
Identification Rules (match/create CIs)
    ↓
CMDB Population

Key Tables

Table	Purpose
discovery_schedule	Discovery schedules
discovery_credentials	Discovery credentials
discovery_range	IP ranges to scan
cmdb_identification_rule	CI identification
ecc_agent	MID Server records
discovery_status	Discovery run status

Discovery Schedules (ES5)

Create Discovery Schedule

// Create discovery schedule (ES5 ONLY!)
var schedule = new GlideRecord("discovery_schedule")
schedule.initialize()

// Basic info
schedule.setValue("name", "Data Center Discovery")
schedule.setValue("description", "Weekly discovery of data center infrastructure")

// Type
schedule.setValue("discover", "IP") // IP, CI, Cloud Resources

// Schedule
schedule.setValue("run_type", "weekly")
schedule.setValue("run_dayofweek", "sunday")
schedule.setValue("run_time", "02:00:00")

// MID Server
schedule.setValue("mid_server", getMIDServerSysId("DataCenterMID"))

// Enable
schedule.setValue("active", true)

var scheduleSysId = schedule.insert()

// Add IP range
addDiscoveryRange(scheduleSysId, "10.0.0.0", "10.0.255.255", "Data Center Network")

Add Discovery Range

// Add IP range to discovery schedule (ES5 ONLY!)
function addDiscoveryRange(scheduleSysId, startIP, endIP, name) {
  var range = new GlideRecord("discovery_range")
  range.initialize()
  range.setValue("schedule", scheduleSysId)
  range.setValue("name", name)
  range.setValue("type", "range")
  range.setValue("range_start", startIP)
  range.setValue("range_end", endIP)
  range.setValue("active", true)
  return range.insert()
}

// Add CIDR range
function addDiscoveryCIDR(scheduleSysId, cidr, name) {
  var range = new GlideRecord("discovery_range")
  range.initialize()
  range.setValue("schedule", scheduleSysId)
  range.setValue("name", name)
  range.setValue("type", "cidr")
  range.setValue("range", cidr) // e.g., '10.0.0.0/24'
  range.setValue("active", true)
  return range.insert()
}