Host

Host Attributes

A host is defined as a computing instance. For example, physical servers, virtual machines, switches or disk array.

Attributes:

Key	Stability	Value Type	Description	Example Values
host.arch		string	The CPU architecture the host system is running on.	amd64; arm32; arm64 (see more)
host.cpu.cache.l2.size		int	The amount of level 2 memory cache available to the processor (in Bytes).	12288000
host.cpu.family		string	Family or generation of the CPU.	6; PA-RISC 1.1e
host.cpu.model.id		string	Model identifier. It provides more granular information about the CPU, distinguishing it from other CPUs within the same family.	6; 9000/778/B180L
host.cpu.model.name		string	Model designation of the processor.	11th Gen Intel(R) Core(TM) i7-1185G7 @ 3.00GHz
host.cpu.stepping		string	Stepping or core revisions.	1; r1p1
host.cpu.vendor.id		string	Processor manufacturer identifier. A maximum 12-character string. [1]	GenuineIntel
host.id		string	Unique host ID, determined by the first matching source in the priority order. [2]	fdbf79e8af94cb7f9e8df36789187052
host.image.id		string	VM image ID or host OS image ID. For Cloud, this value is from the provider.	ami-07b06b442921831e5
host.image.name		string	Name of the VM image or OS install the host was instantiated from.	infra-ami-eks-worker-node-7d4ec78312; CentOS-8-x86_64-1905
host.image.version		string	The version string of the VM image or host OS as defined in Version Attributes.	0.1
host.ip		string[]	Available IP addresses of the host, excluding loopback interfaces. [3]	["192.168.1.140", "fe80::abc2:4a28:737a:609e"]
host.mac		string[]	Available MAC addresses of the host, excluding loopback interfaces. [4]	["AC-DE-48-23-45-67", "AC-DE-48-23-45-67-01-9F"]
host.name		string	Name of the host. On UNIX systems, it may contain what the hostname command returns, or the fully qualified hostname, or another name specified by the user.	opentelemetry-test
host.type		string	Type of host. For Cloud, this must be the machine type.	n1-standard-1

[1] host.cpu.vendor.id: CPUID command returns the vendor ID string in EBX, EDX and ECX registers. Writing these to memory in this order results in a 12-character string.

[2] host.id: SHOULD be determined using the first available source from the following priority tiers:

1. Known cloud vendors - cloud instance ID
2. Known VM vendors - provider VM ID
3. OS-dependent machine ID
4. User-provided value

The value SHOULD conform to the following properties:

• Unique within a given context;
• Repeatable - multiple observers on the same host come up with the same value;
• Persistent - survives host restarts and software updates.

Collecting host.id From Known Environments: When host.id is derived from a cloud vendor instance ID, the resource SHOULD also carry the corresponding cloud.provider and cloud.platform attributes so that the source of the host.id value can be unambiguously determined.

The following cloud environments are currently recognized:

The listed cloud.provider/cloud.platform values are for example only. Refer to the cloud attribute definitions for the relevant set of values.

Non-privileged Machine ID Lookup: When collecting host.id for non-containerized systems, non-privileged lookups of the machine ID are preferred. SDK detector implementations MUST use the sources listed below to obtain the machine ID.

Privileged Machine ID Lookup: The host.id can be looked up using privileged sources. For example, Linux systems can use the output of dmidecode -t system, dmidecode -t baseboard, dmidecode -t chassis, or read the corresponding data from the filesystem (e.g. cat /sys/devices/virtual/dmi/id/product_id, cat /sys/devices/virtual/dmi/id/product_uuid, etc), however, SDK resource detector implementations MUST NOT collect host.id from privileged sources. If privileged lookup of host.id is required, the value SHOULD be injected via the OTEL_RESOURCE_ATTRIBUTES environment variable.

Collecting host.id From User Configuration: If none of the above sources yields a non-empty value, the implementation MAY be unable to determine host.id automatically and SHOULD omit the attribute. In that case, the host.id can only be provided through user configuration or other available manual options. Users SHOULD ensure that the host.id value conforms to the properties stated above.

[3] host.ip: IPv4 Addresses MUST be specified in dotted-quad notation. IPv6 addresses MUST be specified in the RFC 5952 format.

[4] host.mac: MAC Addresses MUST be represented in IEEE RA hexadecimal form: as hyphen-separated octets in uppercase hexadecimal form from most to least significant.

host.arch has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used.

Value	Description	Stability
amd64	AMD64
arm32	ARM32
arm64	ARM64
ia64	Itanium
ppc32	32-bit PowerPC
ppc64	64-bit PowerPC
s390x	IBM z/Architecture
x86	32-bit x86