Host facts

conn3x_host reads facts about a server over SSH when you plan, so the rest of the configuration can depend on them: a package that’s called something else on Debian, a setting sized to the machine’s memory.

data "conn3x_host" "web1" {
  ssh {
    host             = "203.0.113.10"
    user             = "root"
    private_key_file = "~/.ssh/id_ed25519"
  }
}

It takes the same ssh block as a circuit, with host set to the server’s address, and checks the host key the same way.

Attributes

Name	Type	Description
os_family	string	"redhat" or "debian".
os_id	string	The ID from os-release, such as rocky or ubuntu.
os_version	string	The VERSION_ID from os-release, such as 10.0 or 24.04.
arch	string	Machine architecture, such as x86_64 or aarch64.
cpus	number	Number of CPUs.
memory_mb	number	Total memory in MiB.
ipv4	string	Source address of the default IPv4 route, or empty.

Facts for every host in a circuit

Read the facts for each host with for_each, then look them up by the host’s name inside a step:

locals {
  hosts = { web1 = "203.0.113.10", web2 = "203.0.113.11" }
}

data "conn3x_host" "facts" {
  for_each = local.hosts
  ssh {
    host             = each.value
    user             = "root"
    private_key_file = "~/.ssh/id_ed25519"
  }
}

circuit "web" {
  hosts = local.hosts

  ssh {
    user             = "root"
    private_key_file = "~/.ssh/id_ed25519"
  }

  step "apache" {
    package {
      name = data.conn3x_host.facts[each.key].os_family == "debian" ? "apache2" : "httpd"
    }
  }
}

Facts are read fresh on every plan and aren’t stored as anything to change, so they never show up as drift.