fix(instances): a paused VM's guest agent counts as not read

A paused guest cannot answer its agent, so the address search and the VM
report asked it nothing, but counted the VM neither as without an agent
nor as not read: the coverage line read as if every address had been
seen. It now counts among the agents not read, and the line names the
paused case.

instances/addresses.py

@@ -152,14 +152,14 @@ def _read_host(target, network, everything, mac):
     """The cheap first phase on one compute: leases and ARP of each running
     VM in scope (with everything, the shut-off ones are listed too). Returns
     the VMs' records, the observations, the (domain, vm, MACs) whose agent is
-    to be asked, the number of running VMs read and of those without a
-    connected agent; None when the compute cannot be reached (connecting may
+    to be asked, the number of running VMs read, of those without a
+    connected agent, and of paused ones whose agent cannot answer; None when the compute cannot be reached (connecting may
     take the connect timeout, so this too runs on the compute's thread). A
     VM that stops or leaves meanwhile is skipped. With a mac, only the VMs
     with a NIC of that MAC, and only that NIC's addresses."""
     if target.compute.status is not True:
         return None
-    records, found, agents, checked, no_agent = [], [], [], 0, 0
+    records, found, agents, checked, no_agent, paused = [], [], [], 0, 0, 0
     listing = 0 if everything else VIR_CONNECT_LIST_DOMAINS_ACTIVE
     for dom in target.compute.connection.listAllDomains(listing):
         try:
@@ -187,9 +187,11 @@ def _read_host(target, network, everything, mac):
             found += _matching(dom, vm, source, macs, network) or []
         if not agent_connected(xml):
             no_agent += 1
-        elif state == VIR_DOMAIN_RUNNING:  # a paused guest cannot answer
+        elif state == VIR_DOMAIN_RUNNING:
             agents.append((dom, vm, macs))
-    return records, found, agents, checked, no_agent
+        else:
+            paused += 1
+    return records, found, agents, checked, no_agent, paused
 def _rows(observations):
     """One row per VM, MAC and address with its sources; sorted by address.
     A VM is its compute and UUID: one UUID may be defined on two hosts."""
@@ -236,11 +238,12 @@ def _survey(targets, network, deadline, everything, with_os=False, mac=None):
                 if read_host is None:
                     hosts_down.append(hosts[done].name)
                     continue
-                host_records, found, agents, host_checked, host_no_agent = read_host
+                host_records, found, agents, host_checked, host_no_agent, host_paused = read_host
                 records += host_records
                 observations += found
                 checked += host_checked
                 no_agent += host_no_agent
+                unread += host_paused  # a paused guest cannot answer its agent
                 # the OS on its own thread: a hung OS read keeps the addresses read
                 for dom, vm, macs in agents:
                     agent_reads.append(pool.submit(_counted, _matching, dom, vm,

instances/templates/allinstances.html

@@ -54,7 +54,7 @@
          data-unregistered="{% trans "(not registered in the panel)" %}" data-conflict="{% trans "possible conflict" %}"
          data-checked="{% trans "Running VMs checked: %(n)s." %}"
          data-no-agent="{% trans "%(n)s had no connected guest agent; a static address on them cannot be seen." %}"
-         data-unread="{% trans "Guest agents not read (no answer in time, or an error): %(n)s." %}"
+         data-unread="{% trans "Guest agents not read (a paused VM, no answer in time, or an error): %(n)s." %}"
          data-hosts-down="{% trans "Not reached: %(hosts)s." %}"
          data-hosts-unfinished="{% trans "Not finished in time: %(hosts)s." %}"
          data-read-at="{% trans "Read at %(time)s." %}"

instances/tests/test_addresses.py

@@ -171,6 +171,13 @@ class FindTests(unittest.TestCase):
         result = self.find(addresses.Target(c, None))
         self.assertEqual((result["checked"], result["no_agent"]), (2, 1))
 
+    def test_a_paused_vm_with_an_agent_is_an_agent_not_read(self):
+        # a paused guest cannot answer its agent: not "checked and empty"
+        paused = FakeDomain({ARP: {"e": iface(MAC1, (0, "192.0.2.10", 24))}}, state=3)
+        result = self.find(addresses.Target(compute("c1", paused), None))
+        self.assertEqual((result["checked"], result["no_agent"], result["unread"]), (1, 0, 1))
+        self.assertEqual([m["sources"] for m in result["matches"]], [["ARP"]])
+
     def test_a_hung_agent_does_not_hold_the_answer(self):
         hung = threading.Event()
         try:

instances/views.py

@@ -195,7 +195,7 @@ def vm_report(request):
              f"VMs listed: {len(rows)}",
              f"Running VMs read: {result['checked']}",
              f"Without a connected guest agent (a static address on them cannot be seen): {result['no_agent']}",
-             f"Guest agents not read (no answer in time, or an error): {result['unread']}"]
+             f"Guest agents not read (a paused VM, no answer in time, or an error): {result['unread']}"]
     if result["hosts_down"]:
         notes.append("Hosts not reached: " + ", ".join(result["hosts_down"]))
     if result["hosts_unfinished"]: