Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

42 hosts · 339 ms

HostCertsFirst seenLast seenDNS
ionos-group.org 2 2025-10-14 2026-09-30 ok
*.ionos-group.org 2 2025-10-14 2026-09-30 —
traefik-infra-vdc.qa.ionos-group.org 12 2026-05-08 2026-05-16 nxdomain
traefik-cloud-vdc.qa.ionos-group.org 4 2026-05-11 2026-05-16 nxdomain
traefik-auth-vdc.qa.ionos-group.org 4 2026-05-12 2026-05-16 nxdomain
traefik-mail-vdc.qa.ionos-group.org 4 2026-05-11 2026-05-16 nxdomain
argocd.qa.ionos-group.org 12 2026-05-09 2026-05-17 ok
cloud.qa.ionos-group.org 8 2026-05-12 2026-05-17 ok
office-cloud.cloud.qa.ionos-group.org 2 2026-05-19 2026-05-19 ok
ionos-cloud.cloud.qa.ionos-group.org 6 2026-05-13 2026-05-17 ok
office-core.cloud.qa.ionos-group.org 2 2026-05-19 2026-05-19 ok
ionos-core.cloud.qa.ionos-group.org 6 2026-05-13 2026-05-17 ok
lookup.cloud.qa.ionos-group.org 6 2026-05-13 2026-05-17 ok
office-ext.cloud.qa.ionos-group.org 2 2026-05-19 2026-05-19 ok
ionos-ext.cloud.qa.ionos-group.org 6 2026-05-13 2026-05-17 ok
monitoring.qa.ionos-group.org 12 2026-05-09 2026-05-17 ok
auth.qa.ionos-group.org 8 2026-05-08 2026-05-17 ok
linstor-gui.qa.ionos-group.org 2 2026-05-12 2026-05-12 nxdomain
mail.qa.ionos-group.org 8 2026-05-16 2026-05-17 ok
mx-fra.mail.qa.ionos-group.org 8 2026-05-16 2026-05-17 nxdomain
linstor.mail.qa.ionos-group.org 6 2026-05-12 2026-05-17 nxdomain
smtp.qa.ionos-group.org 8 2026-05-16 2026-05-17 ok
rancher.qa.ionos-group.org 4 2026-05-10 2026-05-17 ok
mta-sts.qa.ionos-group.org 10 2026-05-08 2026-05-17 ok
cloud.ncpoc.ionos-group.org 5 2026-05-26 2026-09-23 ok
office.ncpoc.ionos-group.org 5 2026-05-26 2026-09-13 ok
signaling.ncpoc.ionos-group.org 5 2026-05-30 2026-09-27 ok
workspace.ionos-group.org 1 2026-08-21 2026-08-21 nodata
*.workspace.ionos-group.org 1 2026-08-21 2026-08-21 —
ionosgroup-devolutions-encryption-service.ionos-group.org 1 2025-10-07 2025-10-07 ok
www.ionosgroup-devolutions-encryption-service.ionos-group.org 1 2025-10-07 2025-10-07 nxdomain
traefik-infra-vdc.prelive.ionos-group.org 2 2026-05-06 2026-05-06 nxdomain
argocd.prelive.ionos-group.org 4 2026-05-04 2026-05-06 nxdomain
monitoring.prelive.ionos-group.org 12 2026-05-05 2026-05-08 nxdomain
auth.prelive.ionos-group.org 2 2026-05-05 2026-05-05 nxdomain
mta-sts.prelive.ionos-group.org 2 2026-05-06 2026-05-06 nxdomain
pki.ionos-group.org 2 2025-10-08 2026-09-17 nodata
www.pki.ionos-group.org 2 2025-10-08 2026-09-17 nodata
keycloak.poc.test.ionos-group.org 2 2026-04-30 2026-04-30 ok
wildduck.poc.test.ionos-group.org 2 2026-04-30 2026-04-30 nodata
dovecot.poc.test.ionos-group.org 2 2026-04-30 2026-04-30 nodata
stalwart.poc.test.ionos-group.org 2 2026-04-30 2026-04-30 ok

Programmatic access, with DNS A records: API GET /v1/hosts/ionos-group.org (API key for paging).

Shown here: hostnames with a certificate that is valid now or expired within the last 90 days. The full history since 2013 — hostnames whose last certificate expired earlier — is a Pro plan method: GET /v1/hosts-history/ionos-group.org.