diff --git a/src/ch/virtchd.service.in b/src/ch/virtchd.service.in
index 6e3b13446f..22314bc907 100644
--- a/src/ch/virtchd.service.in
+++ b/src/ch/virtchd.service.in
@@ -22,11 +22,10 @@ ExecStart=@sbindir@/virtchd $VIRTCHD_ARGS
 ExecReload=/bin/kill -HUP $MAINPID
 KillMode=process
 Restart=on-failure
-# At least 2 FD per guest (eg ch monitor + ch socket).
-# eg if we want to support 4096 guests, we'll typically need 8192 FDs
-# If changing this, also consider virtlogd.service & virtlockd.service
-# limits which are also related to number of guests
-LimitNOFILE=8192
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 # The cgroups pids controller can limit the number of tasks started by
 # the daemon, which can limit the number of domains for some hypervisors.
 # A conservative default of 8 tasks per guest results in a TasksMax of
diff --git a/src/locking/virtlockd.service.in b/src/locking/virtlockd.service.in
index 23054369d5..f1792dcb43 100644
--- a/src/locking/virtlockd.service.in
+++ b/src/locking/virtlockd.service.in
@@ -15,10 +15,10 @@ ExecReload=/bin/kill -USR1 $MAINPID
 # cause the machine to be fenced (rebooted), so make
 # sure we discourage OOM killer
 OOMScoreAdjust=-900
-# Needs to allow for max guests * average disks per guest
-# libvirtd.service written to expect 4096 guests, so if we
-# allow for 10 disks per guest, we get:
-LimitNOFILE=40960
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 
 [Install]
 Also=virtlockd.socket
diff --git a/src/logging/virtlogd.service.in b/src/logging/virtlogd.service.in
index e4aecd46a7..cef4053f59 100644
--- a/src/logging/virtlogd.service.in
+++ b/src/logging/virtlogd.service.in
@@ -15,13 +15,10 @@ ExecReload=/bin/kill -USR1 $MAINPID
 # cause the machine to be fenced (rebooted), so make
 # sure we discourage OOM killer
 OOMScoreAdjust=-900
-# Need to have at least one file open per guest (eg QEMU
-# stdio log), but might be more (eg serial console logs)
-# A common case is OpenStack which often has up to 4 file
-# handles per guest.
-# libvirtd.service written to expect 4096 guests, so if we
-# guess at 4 files per guest here that is 16k:
-LimitNOFILE=16384
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 
 [Install]
 Also=virtlogd.socket
diff --git a/src/lxc/virtlxcd.service.in b/src/lxc/virtlxcd.service.in
index 06c70ccde2..59d7d26657 100644
--- a/src/lxc/virtlxcd.service.in
+++ b/src/lxc/virtlxcd.service.in
@@ -22,11 +22,10 @@ ExecStart=@sbindir@/virtlxcd $VIRTLXCD_ARGS
 ExecReload=/bin/kill -HUP $MAINPID
 KillMode=process
 Restart=on-failure
-# At least 1 FD per guest, often 2 (eg qemu monitor + qemu agent).
-# eg if we want to support 4096 guests, we'll typically need 8192 FDs
-# If changing this, also consider virtlogd.service & virtlockd.service
-# limits which are also related to number of guests
-LimitNOFILE=8192
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 # The cgroups pids controller can limit the number of tasks started by
 # the daemon, which can limit the number of domains for some hypervisors.
 # A conservative default of 8 tasks per guest results in a TasksMax of
diff --git a/src/qemu/virtqemud.service.in b/src/qemu/virtqemud.service.in
index 46917b746d..7e02f7ab51 100644
--- a/src/qemu/virtqemud.service.in
+++ b/src/qemu/virtqemud.service.in
@@ -24,11 +24,10 @@ ExecStart=@sbindir@/virtqemud $VIRTQEMUD_ARGS
 ExecReload=/bin/kill -HUP $MAINPID
 KillMode=process
 Restart=on-failure
-# At least 1 FD per guest, often 2 (eg qemu monitor + qemu agent).
-# eg if we want to support 4096 guests, we'll typically need 8192 FDs
-# If changing this, also consider virtlogd.service & virtlockd.service
-# limits which are also related to number of guests
-LimitNOFILE=8192
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 # The cgroups pids controller can limit the number of tasks started by
 # the daemon, which can limit the number of domains for some hypervisors.
 # A conservative default of 8 tasks per guest results in a TasksMax of
diff --git a/src/remote/libvirtd.service.in b/src/remote/libvirtd.service.in
index afda257228..28bcdb1220 100644
--- a/src/remote/libvirtd.service.in
+++ b/src/remote/libvirtd.service.in
@@ -29,11 +29,10 @@ ExecStart=@sbindir@/libvirtd $LIBVIRTD_ARGS
 ExecReload=/bin/kill -HUP $MAINPID
 KillMode=process
 Restart=on-failure
-# At least 1 FD per guest, often 2 (eg qemu monitor + qemu agent).
-# eg if we want to support 4096 guests, we'll typically need 8192 FDs
-# If changing this, also consider virtlogd.service & virtlockd.service
-# limits which are also related to number of guests
-LimitNOFILE=8192
+# Raise hard limits to match behaviour of systemd >= 240.
+# During startup, daemon will set soft limit to match hard limit
+# per systemd recommendations
+LimitNOFile=512000:1024
 # The cgroups pids controller can limit the number of tasks started by
 # the daemon, which can limit the number of domains for some hypervisors.
 # A conservative default of 8 tasks per guest results in a TasksMax of