-cache/iface.%: cache/bridge.$$(call get,%)
- @echo "Creating interface for link $(call proj1,$*) on $(call get,$*)"
- @$(SSH) $(HOST_$(call get,$*)) \
- $(SUDO) sliver-ovs create-port $$(cat $^) L$(call proj1,$*) > $@ \
+# cache/iface.<node_id1>-<node_id2>@<endpoint>:
+# Creates the interface for link <node_id1>-<node_id2> on
+# <node_id<endpoint>>.
+#
+# The bridge of the local node must already exist, and we need to create
+# the interface again if the bridge is re-created.
+# We also need a running db daemon, but we do not need to do anything
+# if the db daemon is restarted.
+cache/iface.%: cache/bridge.$$(call get,%) | cache/db.$$(call get,%)
+ @echo "Creating interface for link $(call linkpart,$(*F)) on $(call display,$(call get,$(*F))) - logs in $(call log,$@)"
+ @$(SSH) $(call solve,$(call get,$(*F))) $(SUDO) sliver-ovs create-port $(BRIDGE) \
+ L$(call linkpart,$(*F)) &> $(call log,$@) \
+ && touch $@
+
+# cache/port.<node_id1>-<node_id2>@<endpoint>:
+# Retrieves the local port of link <node_id1>-<node_id2> on
+# node <node_id<endpoint>>.
+#
+# The local interface must have been created already and the
+# switch daemon must be running. We need to retrieve the port
+# number again if the interface is re-created, or the switch
+# daemon is restarted.
+cache/port.%: cache/iface.% cache/switch.$$(call get,%)
+ @echo "Getting port number for link $(call linkpart,$(*F)) on $(call display,$(call get,$(*F))) - logs in $(call log,$@)"
+ @$(SSH) $(call solve,$(call get,$(*F))) $(SUDO) \
+ ovs-appctl netdev-tunnel/get-port L$(call linkpart,$(*F)) > $@ 2> $(call log,$@) \