{"source":"semconv","version":"1.44.0","attribute":{"id":"service.instance.id","type":"string","stability":"stable","brief":"The string ID of the service instance.","note":"MUST be unique for each instance of the same `service.namespace,service.name` pair (in other words\n`service.namespace,service.name,service.instance.id` triplet MUST be globally unique). The ID helps to\ndistinguish instances of the same service that exist at the same time (e.g. instances of a horizontally scaled\nservice).\n\nImplementations, such as SDKs, are recommended to generate a random Version 1 or Version 4 [RFC\n4122](https://www.ietf.org/rfc/rfc4122.txt) UUID, but are free to use an inherent unique ID as the source of\nthis value if stability is desirable. In that case, the ID SHOULD be used as source of a UUID Version 5 and\nSHOULD use the following UUID as the namespace: `4d63009a-8d0f-11ee-aad7-4c796ed8e320`.\n\nUUIDs are typically recommended, as only an opaque value for the purposes of identifying a service instance is\nneeded. Similar to what can be seen in the man page for the\n[`/etc/machine-id`](https://www.freedesktop.org/software/systemd/man/latest/machine-id.html) file, the underlying\ndata, such as pod name and namespace should be treated as confidential, being the user's choice to expose it\nor not via another resource attribute.\n\nFor applications running behind an application server (like unicorn), we do not recommend using one identifier\nfor all processes participating in the application. Instead, it's recommended each division (e.g. a worker\nthread in unicorn) to have its own instance.id.\n\nIt's not recommended for a Collector to set `service.instance.id` if it can't unambiguously determine the\nservice instance that is generating that telemetry. For instance, creating an UUID based on `pod.name` will\nlikely be wrong, as the Collector might not know from which container within that pod the telemetry originated.\nHowever, Collectors can set the `service.instance.id` if they can unambiguously determine the service instance\nfor that telemetry. This is typically the case for scraping receivers, as they know the target address and\nport.","examples":["627cc493-f310-47de-96bd-71410b7dec09"],"namespace":"service","definedIn":"model/service/registry.yaml","usedBy":[{"groupId":"entity.service.instance","groupType":"entity","signalName":"service.instance","requirementLevel":"required"},{"groupId":"service.zos.software","groupType":"attribute_group","signalName":"service.zos.software","requirementLevel":"required"}]},"history":[{"version":"1.30.0","publishedAt":"2025-01-24T19:11:42Z","kind":"first-seen","detail":"Already present at v1.30.0, the oldest release tracked here (experimental)."},{"version":"1.31.0","publishedAt":"2025-03-11T00:53:13Z","kind":"stability-changed","detail":"Stability label respelled from experimental to development.","severity":"informational"},{"version":"1.40.0","publishedAt":"2026-02-19T17:50:21Z","kind":"stability-changed","detail":"Promoted to stable.","severity":"notable"}],"replaces":[]}