L2BridgingComponent.java ternary match problem

[makrofag1]

Hi,
I have observed this ONOS warn in onos logs:
Unable to INSERT table entry on device:leaf2: OTHER_ERROR INVALID_ARGUMENT Invalid representation of 'don't care' ternary match, omit match field instead of using 0 mask (:3) [PiTableEntry{tableId=IngressPipeImpl.l2_ternary_table, matchKey={hdr.ethernet.dst_addr=0x0&&&0x0}, tableAction=IngressPipeImpl.set_multicast_group(gid=0xff), priority=11, timeout=PERMANENT}]

This warn lead me to L2BridgingComponent.java file where we can find criterion that should match any previously unmatched packet (lines 272 - 277). Could you explain me please what is the proper representation of the rule that matches anything? I use onos 2.2.2 and mentioned rule stays in pending add.
@bocon13 @ccascone

[charlesmcchan]

The error message seems suggesting that we should omit the entire match field instead of using wildcard mask.
Have you tried removing the entire match field on hdr.ethernet.dst?

[makrofag1]

I have removed hdr.ethernet.dst, so the criterion looks like this:
final PiCriterion unmatchedTrafficCriterion = PiCriterion.builder() .matchTernary( PiMatchFieldId.of(""), MacAddress.valueOf("00:00:00:00:00:00").toBytes(), MacAddress.valueOf("00:00:00:00:00:00").toBytes()) .build();

In the result I have received this exception in onos logs:
Exception in thread "pool-13-thread-3" java.lang.IllegalArgumentException: Name cannot be empty at com.google.common.base.Preconditions.checkArgument(Preconditions.java:134) at org.onosproject.net.pi.model.PiMatchFieldId.of(PiMatchFieldId.java:43) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.insertUnmatchedBridgingFlowRule(L2BridgingComponent.java:274) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.setUpDevice(L2BridgingComponent.java:158) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.lambda$setUpAllDevices$2(L2BridgingComponent.java:496) at com.google.common.collect.Iterables$4.lambda$forEach$0(Iterables.java:584) at java.base/java.util.concurrent.ConcurrentHashMap$ValuesView.forEach(ConcurrentHashMap.java:4772) at java.base/java.util.Collections$UnmodifiableCollection.forEach(Collections.java:1085) at com.google.common.collect.Iterables$4.forEach(Iterables.java:581) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.setUpAllDevices(L2BridgingComponent.java:493) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829)

There is no way to omit entire object of PiMatchFieldID.of() because in PiCriterion which is used in L2BridingComponent.java all versions of matchTernary() function require 3 arguments. I really don't understand why it doesn't work despite it is a tutorial.

[charlesmcchan]

I was suggesting skipping the entire ethernet dst match field. Something like this:

final PiCriterion unmatchedTrafficCriterion = PiCriterion.builder().build();

This should theoretically create a "catch all" match

[makrofag1]

I checked your suggestion but I get:
Exception in thread "pool-13-thread-3" java.lang.IllegalArgumentException: Cannot build PI criterion with 0 field matches at com.google.common.base.Preconditions.checkArgument(Preconditions.java:134) at org.onosproject.net.flow.criteria.PiCriterion$Builder.build(PiCriterion.java:334) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.insertUnmatchedBridgingFlowRule(L2BridgingComponent.java:272) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.setUpDevice(L2BridgingComponent.java:158) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.lambda$setUpAllDevices$2(L2BridgingComponent.java:491) at com.google.common.collect.Iterables$4.lambda$forEach$0(Iterables.java:584) at java.base/java.util.concurrent.ConcurrentHashMap$ValuesView.forEach(ConcurrentHashMap.java:4772) at java.base/java.util.Collections$UnmodifiableCollection.forEach(Collections.java:1085) at com.google.common.collect.Iterables$4.forEach(Iterables.java:581) at org.onosproject.ngsdn.tutorial.L2BridgingComponent.setUpAllDevices(L2BridgingComponent.java:488) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)

[charlesmcchan]

Hmm... alright, looks like it doesn't like it either. Will need to take a closer look to figure out why the original PiCriterion get rejected.

[ccascone]

Hi @makrofag1, you are describing the case where an app wants to modify a table's default action, which is equivalent to a flow rule with all match fields set to "don't care". To create such a flow rule, you simply need to omit adding a selector when invoking the flow rule builder. Unfortunately, in this tutorial we use the utility method buildFlowRule which always adds a selector:

ngsdn-tutorial/app/src/main/java/org/onosproject/ngsdn/tutorial/common/Utils.java

Line 110 in 62705c3

.withSelector(DefaultTrafficSelector.builder()

You could solve this by creating a different utility method that looks like this:

public static FlowRule buildFlowRuleDefaultAction(DeviceId switchId, ApplicationId appId,
                                                  String tableId, PiTableAction piAction) {
        return DefaultFlowRule.builder()
                .forDevice(switchId)
                .forTable(PiTableId.of(tableId))
                .fromApp(appId)
                .withPriority(DEFAULT_FLOW_RULE_PRIORITY)
                .makePermanent(
                .withTreatment(DefaultTrafficTreatment.builder()
                                       .piTableAction(piAction).build())
                .build();
    }