flow/

README

Protocol Documentation

Table of Contents

• flow/flow.proto

  • AgentEvent

  • AgentEventUnknown

  • CiliumEventType

  • DNS

  • DebugEvent

  • Endpoint

  • EndpointRegenNotification

  • EndpointUpdateNotification

  • Ethernet

  • EventTypeFilter

  • Flow

  • FlowFilter

  • HTTP

  • HTTPHeader

  • ICMPv4

  • ICMPv6

  • IP

  • IPCacheNotification

  • Kafka

  • Layer4

  • Layer7

  • LostEvent

  • NetworkInterface

  • Policy

  • PolicyUpdateNotification

  • SCTP

  • Service

  • ServiceDeleteNotification

  • ServiceUpsertNotification

  • ServiceUpsertNotificationAddr

  • TCP

  • TCPFlags

  • TimeNotification

  • TraceContext

  • TraceParent

  • UDP

  • Workload

  • AgentEventType

  • AuthType

  • DebugCapturePoint

  • DebugEventType

  • DropReason

  • EventType

  • FlowType

  • IPVersion

  • L7FlowType

  • LostEventSource

  • SocketTranslationPoint

  • TraceObservationPoint

  • TrafficDirection

  • Verdict

• Scalar Value Types

Top

flow/flow.proto

AgentEvent

Field	Type	Label	Description
type	AgentEventType
unknown	AgentEventUnknown
agent_start	TimeNotification
policy_update	PolicyUpdateNotification		used for POLICY_UPDATED and POLICY_DELETED
endpoint_regenerate	EndpointRegenNotification		used for ENDPOINT_REGENERATE_SUCCESS and ENDPOINT_REGENERATE_FAILURE
endpoint_update	EndpointUpdateNotification		used for ENDPOINT_CREATED and ENDPOINT_DELETED
ipcache_update	IPCacheNotification		used for IPCACHE_UPSERTED and IPCACHE_DELETED
service_upsert	ServiceUpsertNotification
service_delete	ServiceDeleteNotification

AgentEventUnknown

Field	Type	Label	Description
type	string
notification	string

CiliumEventType

CiliumEventType from which the flow originated.

Field	Type	Label	Description
type	int32		type of event the flow originated from, i.e. github.com/cilium/cilium/pkg/monitor/api.MessageType*
sub_type	int32		sub_type may indicate more details depending on type, e.g. - github.com/cilium/cilium/pkg/monitor/api.Trace* - github.com/cilium/cilium/pkg/monitor/api.Drop* - github.com/cilium/cilium/pkg/monitor/api.DbgCapture*

DNS

DNS flow. This is basically directly mapped from Cilium's LogRecordDNS:

Field	Type	Label	Description
query	string		DNS name that's being looked up: e.g. "isovalent.com."
ips	string	repeated	List of IP addresses in the DNS response.
ttl	uint32		TTL in the DNS response.
cnames	string	repeated	List of CNames in the DNS response.
observation_source	string		Corresponds to DNSDataSource defined in: https://github.com/cilium/cilium/blob/04f3889d627774f79e56d14ddbc165b3169e2d01/pkg/proxy/accesslog/record.go#L253
rcode	uint32		Return code of the DNS request defined in: https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-6
qtypes	string	repeated	String representation of qtypes defined in: https://tools.ietf.org/html/rfc1035#section-3.2.3
rrtypes	string	repeated	String representation of rrtypes defined in: https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-4

DebugEvent

Field	Type	Label	Description
type	DebugEventType
source	Endpoint
hash	google.protobuf.UInt32Value
arg1	google.protobuf.UInt32Value
arg2	google.protobuf.UInt32Value
arg3	google.protobuf.UInt32Value
message	string
cpu	google.protobuf.Int32Value

Endpoint

Field	Type	Label	Description
ID	uint32
identity	uint32
namespace	string
labels	string	repeated	labels in foo=bar format.
pod_name	string
workloads	Workload	repeated

EndpointRegenNotification

Field	Type	Label	Description
id	uint64
labels	string	repeated
error	string

EndpointUpdateNotification

Field	Type	Label	Description
id	uint64
labels	string	repeated
error	string
pod_name	string
namespace	string

Ethernet

Field	Type	Label	Description
source	string
destination	string

EventTypeFilter

EventTypeFilter is a filter describing a particular event type.

Field	Type	Label	Description
type	int32		type is the primary flow type as defined by: github.com/cilium/cilium/pkg/monitor/api.MessageType*
match_sub_type	bool		match_sub_type is set to true when matching on the sub_type should be done. This flag is required as 0 is a valid sub_type.
sub_type	int32		sub_type is the secondary type, e.g. - github.com/cilium/cilium/pkg/monitor/api.Trace*

Flow

Field	Type	Label	Description
time	google.protobuf.Timestamp
uuid	string		uuid is a universally unique identifier for this flow.
verdict	Verdict
drop_reason	uint32		Deprecated. only applicable to Verdict = DROPPED. deprecated in favor of drop_reason_desc.
auth_type	AuthType		auth_type is the authentication type specified for the flow in Cilium Network Policy. Only set on policy verdict events.
ethernet	Ethernet		l2
IP	IP		l3
l4	Layer4		l4
source	Endpoint
destination	Endpoint
Type	FlowType
node_name	string		NodeName is the name of the node from which this Flow was captured.
source_names	string	repeated	all names the source IP can have.
destination_names	string	repeated	all names the destination IP can have.
l7	Layer7		L7 information. This field is set if and only if FlowType is L7.
reply	bool		Deprecated. Deprecated. This suffers from false negatives due to protobuf not being able to distinguish between the value being false or it being absent. Please use is_reply instead.
event_type	CiliumEventType		EventType of the originating Cilium event
source_service	Service		source_service contains the service name of the source
destination_service	Service		destination_service contains the service name of the destination
traffic_direction	TrafficDirection		traffic_direction of the connection, e.g. ingress or egress
policy_match_type	uint32		policy_match_type is only applicable to the cilium event type PolicyVerdict https://github.com/cilium/cilium/blob/e831859b5cc336c6d964a6d35bbd34d1840e21b9/pkg/monitor/datapath_policy.go#L50
trace_observation_point	TraceObservationPoint		Only applicable to cilium trace notifications, blank for other types.
drop_reason_desc	DropReason		only applicable to Verdict = DROPPED.
is_reply	google.protobuf.BoolValue		is_reply indicates that this was a packet (L4) or message (L7) in the reply direction. May be absent (in which case it is unknown whether it is a reply or not).
debug_capture_point	DebugCapturePoint		Only applicable to cilium debug capture events, blank for other types
interface	NetworkInterface		interface is the network interface on which this flow was observed
proxy_port	uint32		proxy_port indicates the port of the proxy to which the flow was forwarded
trace_context	TraceContext		trace_context contains information about a trace related to the flow, if any.
sock_xlate_point	SocketTranslationPoint		sock_xlate_point is the socket translation point. Only applicable to TraceSock notifications, blank for other types
socket_cookie	uint64		socket_cookie is the Linux kernel socket cookie for this flow. Only applicable to TraceSock notifications, zero for other types
cgroup_id	uint64		cgroup_id of the process which emitted this event. Only applicable to TraceSock notifications, zero for other types
Summary	string		Deprecated. This is a temporary workaround to support summary field for pb.Flow without duplicating logic from the old parser. This field will be removed once we fully migrate to the new parser.
extensions	google.protobuf.Any		extensions can be used to add arbitrary additional metadata to flows. This can be used to extend functionality for other Hubble compatible APIs, or experiment with new functionality without needing to change the public API.
egress_allowed_by	Policy	repeated	The CiliumNetworkPolicies allowing the egress of the flow.
ingress_allowed_by	Policy	repeated	The CiliumNetworkPolicies allowing the ingress of the flow.

FlowFilter

FlowFilter represent an individual flow filter. All fields are optional. If multiple fields are set, then all fields must match for the filter to match.

Field	Type	Label	Description
uuid	string	repeated	uuid filters by a list of flow uuids.
source_ip	string	repeated	source_ip filters by a list of source ips. Each of the source ips can be specified as an exact match (e.g. "1.1.1.1") or as a CIDR range (e.g. "1.1.1.0/24").
source_pod	string	repeated	source_pod filters by a list of source pod name prefixes, optionally within a given namespace (e.g. "xwing", "kube-system/coredns-"). The pod name can be omitted to only filter by namespace (e.g. "kube-system/") or the namespace can be omitted to filter for pods in any namespace (e.g. "/xwing")
source_fqdn	string	repeated	source_fqdn filters by a list of source fully qualified domain names
source_label	string	repeated	source_labels filters on a list of source label selectors. Selectors support the full Kubernetes label selector syntax.
source_service	string	repeated	source_service filters on a list of source service names. This field supports the same syntax as the source_pod field.
source_workload	Workload	repeated	source_workload filters by a list of source workload.
destination_ip	string	repeated	destination_ip filters by a list of destination ips. Each of the destination ips can be specified as an exact match (e.g. "1.1.1.1") or as a CIDR range (e.g. "1.1.1.0/24").
destination_pod	string	repeated	destination_pod filters by a list of destination pod names
destination_fqdn	string	repeated	destination_fqdn filters by a list of destination fully qualified domain names
destination_label	string	repeated	destination_label filters on a list of destination label selectors
destination_service	string	repeated	destination_service filters on a list of destination service names
destination_workload	Workload	repeated	destination_workload filters by a list of destination workload.
traffic_direction	TrafficDirection	repeated	traffic_direction filters flow by direction of the connection, e.g. ingress or egress.
verdict	Verdict	repeated	only return Flows that were classified with a particular verdict.
event_type	EventTypeFilter	repeated	event_type is the list of event types to filter on
http_status_code	string	repeated	http_status_code is a list of string prefixes (e.g. "4+", "404", "5+") to filter on the HTTP status code
protocol	string	repeated	protocol filters flows by L4 or L7 protocol, e.g. (e.g. "tcp", "http")
source_port	string	repeated	source_port filters flows by L4 source port
destination_port	string	repeated	destination_port filters flows by L4 destination port
reply	bool	repeated	reply filters flows based on the direction of the flow.
dns_query	string	repeated	dns_query filters L7 DNS flows by query patterns (RE2 regex), e.g. 'kube.*local'.
source_identity	uint32	repeated	source_identity filters by the security identity of the source endpoint.
destination_identity	uint32	repeated	destination_identity filters by the security identity of the destination endpoint.
http_method	string	repeated	GET, POST, PUT, etc. methods. This type of field is well suited for an enum but every single existing place is using a string already.
http_path	string	repeated	http_path is a list of regular expressions to filter on the HTTP path.
http_url	string	repeated	http_url is a list of regular expressions to filter on the HTTP URL.
http_header	HTTPHeader	repeated	http_header is a list of key:value pairs to filter on the HTTP headers.
tcp_flags	TCPFlags	repeated	tcp_flags filters flows based on TCP header flags
node_name	string	repeated	node_name is a list of patterns to filter on the node name, e.g. "k8s*", "test-cluster/*.domain.com", "cluster-name/" etc.
ip_version	IPVersion	repeated	filter based on IP version (ipv4 or ipv6)
trace_id	string	repeated	trace_id filters flows by trace ID

HTTP

L7 information for HTTP flows. It corresponds to Cilium's accesslog.LogRecordHTTP type.

Field	Type	Label	Description
code	uint32
method	string
url	string
protocol	string
headers	HTTPHeader	repeated

HTTPHeader

Field	Type	Label	Description
key	string
value	string

ICMPv4

Field	Type	Label	Description
type	uint32
code	uint32

ICMPv6

Field	Type	Label	Description
type	uint32
code	uint32

IP

Field	Type	Label	Description
source	string
destination	string
ipVersion	IPVersion
encrypted	bool		This field indicates whether the TraceReasonEncryptMask is set or not. https://github.com/cilium/cilium/blob/ba0ed147bd5bb342f67b1794c2ad13c6e99d5236/pkg/monitor/datapath_trace.go#L27

IPCacheNotification

Field	Type	Label	Description
cidr	string
identity	uint32
old_identity	google.protobuf.UInt32Value
host_ip	string
old_host_ip	string
encrypt_key	uint32
namespace	string
pod_name	string

Kafka

L7 information for Kafka flows. It corresponds to Cilium's accesslog.LogRecordKafka type.

Field	Type	Label	Description
error_code	int32
api_version	int32
api_key	string
correlation_id	int32
topic	string

Layer4

Field	Type	Label	Description
TCP	TCP
UDP	UDP
ICMPv4	ICMPv4		ICMP is technically not L4, but mutually exclusive with the above
ICMPv6	ICMPv6
SCTP	SCTP

Layer7

Message for L7 flow, which roughly corresponds to Cilium's accesslog LogRecord:

Field	Type	Label	Description
type	L7FlowType
latency_ns	uint64		Latency of the response
dns	DNS
http	HTTP
kafka	Kafka

LostEvent

LostEvent is a message which notifies consumers about a loss of events that happened before the events were captured by Hubble.

Field	Type	Label	Description
source	LostEventSource		source is the location where events got lost.
num_events_lost	uint64		num_events_lost is the number of events that haven been lost at source.
cpu	google.protobuf.Int32Value		cpu on which the event was lost if the source of lost events is PERF_EVENT_RING_BUFFER.

NetworkInterface

Field	Type	Label	Description
index	uint32
name	string

Policy

Field	Type	Label	Description
name	string
namespace	string
labels	string	repeated
revision	uint64

PolicyUpdateNotification

Field	Type	Label	Description
labels	string	repeated
revision	uint64
rule_count	int64

SCTP

Field	Type	Label	Description
source_port	uint32
destination_port	uint32

Service

Field	Type	Label	Description
name	string
namespace	string

ServiceDeleteNotification

Field	Type	Label	Description
id	uint32

ServiceUpsertNotification

Field	Type	Label	Description
id	uint32
frontend_address	ServiceUpsertNotificationAddr
backend_addresses	ServiceUpsertNotificationAddr	repeated
type	string
traffic_policy	string		Deprecated.
name	string
namespace	string
ext_traffic_policy	string
int_traffic_policy	string

ServiceUpsertNotificationAddr

Field	Type	Label	Description
ip	string
port	uint32

TCP

Field	Type	Label	Description
source_port	uint32
destination_port	uint32
flags	TCPFlags

TCPFlags

Field	Type	Label	Description
FIN	bool
SYN	bool
RST	bool
PSH	bool
ACK	bool
URG	bool
ECE	bool
CWR	bool
NS	bool

TimeNotification

Field	Type	Label	Description
time	google.protobuf.Timestamp

TraceContext

TraceContext contains trace context propagation data, i.e. information about a distributed trace. For more information about trace context, check the W3C Trace Context specification.

Field	Type	Label	Description
parent	TraceParent		parent identifies the incoming request in a tracing system.

TraceParent

TraceParent identifies the incoming request in a tracing system.

Field	Type	Label	Description
trace_id	string		trace_id is a unique value that identifies a trace. It is a byte array represented as a hex string.

UDP

Field	Type	Label	Description
source_port	uint32
destination_port	uint32

Workload

Field	Type	Label	Description
name	string
kind	string

AgentEventType

AgentEventType is the type of agent event. These values are shared with type AgentNotification in pkg/monitor/api/types.go.

Name	Number	Description
AGENT_EVENT_UNKNOWN	0
AGENT_STARTED	2
POLICY_UPDATED	3
POLICY_DELETED	4
ENDPOINT_REGENERATE_SUCCESS	5
ENDPOINT_REGENERATE_FAILURE	6
ENDPOINT_CREATED	7
ENDPOINT_DELETED	8
IPCACHE_UPSERTED	9
IPCACHE_DELETED	10
SERVICE_UPSERTED	11
SERVICE_DELETED	12

AuthType

These types correspond to definitions in pkg/policy/l4.go.

Name	Number	Description
DISABLED	0
SPIRE	1
TEST_ALWAYS_FAIL	2

DebugCapturePoint

These values are shared with pkg/monitor/api/datapath_debug.go and bpf/lib/dbg.h.

Name	Number	Description
DBG_CAPTURE_POINT_UNKNOWN	0
DBG_CAPTURE_DELIVERY	4
DBG_CAPTURE_FROM_LB	5
DBG_CAPTURE_AFTER_V46	6
DBG_CAPTURE_AFTER_V64	7
DBG_CAPTURE_PROXY_PRE	8
DBG_CAPTURE_PROXY_POST	9
DBG_CAPTURE_SNAT_PRE	10
DBG_CAPTURE_SNAT_POST	11

DebugEventType

These values are shared with pkg/monitor/api/datapath_debug.go and bpf/lib/dbg.h.

Name	Number	Description
DBG_EVENT_UNKNOWN	0
DBG_GENERIC	1
DBG_LOCAL_DELIVERY	2
DBG_ENCAP	3
DBG_LXC_FOUND	4
DBG_POLICY_DENIED	5
DBG_CT_LOOKUP	6
DBG_CT_LOOKUP_REV	7
DBG_CT_MATCH	8
DBG_CT_CREATED	9
DBG_CT_CREATED2	10
DBG_ICMP6_HANDLE	11
DBG_ICMP6_REQUEST	12
DBG_ICMP6_NS	13
DBG_ICMP6_TIME_EXCEEDED	14
DBG_CT_VERDICT	15
DBG_DECAP	16
DBG_PORT_MAP	17
DBG_ERROR_RET	18
DBG_TO_HOST	19
DBG_TO_STACK	20
DBG_PKT_HASH	21
DBG_LB6_LOOKUP_FRONTEND	22
DBG_LB6_LOOKUP_FRONTEND_FAIL	23
DBG_LB6_LOOKUP_BACKEND_SLOT	24
DBG_LB6_LOOKUP_BACKEND_SLOT_SUCCESS	25
DBG_LB6_LOOKUP_BACKEND_SLOT_V2_FAIL	26
DBG_LB6_LOOKUP_BACKEND_FAIL	27
DBG_LB6_REVERSE_NAT_LOOKUP	28
DBG_LB6_REVERSE_NAT	29
DBG_LB4_LOOKUP_FRONTEND	30
DBG_LB4_LOOKUP_FRONTEND_FAIL	31
DBG_LB4_LOOKUP_BACKEND_SLOT	32
DBG_LB4_LOOKUP_BACKEND_SLOT_SUCCESS	33
DBG_LB4_LOOKUP_BACKEND_SLOT_V2_FAIL	34
DBG_LB4_LOOKUP_BACKEND_FAIL	35
DBG_LB4_REVERSE_NAT_LOOKUP	36
DBG_LB4_REVERSE_NAT	37
DBG_LB4_LOOPBACK_SNAT	38
DBG_LB4_LOOPBACK_SNAT_REV	39
DBG_CT_LOOKUP4	40
DBG_RR_BACKEND_SLOT_SEL	41
DBG_REV_PROXY_LOOKUP	42
DBG_REV_PROXY_FOUND	43
DBG_REV_PROXY_UPDATE	44
DBG_L4_POLICY	45
DBG_NETDEV_IN_CLUSTER	46
DBG_NETDEV_ENCAP4	47
DBG_CT_LOOKUP4_1	48
DBG_CT_LOOKUP4_2	49
DBG_CT_CREATED4	50
DBG_CT_LOOKUP6_1	51
DBG_CT_LOOKUP6_2	52
DBG_CT_CREATED6	53
DBG_SKIP_PROXY	54
DBG_L4_CREATE	55
DBG_IP_ID_MAP_FAILED4	56
DBG_IP_ID_MAP_FAILED6	57
DBG_IP_ID_MAP_SUCCEED4	58
DBG_IP_ID_MAP_SUCCEED6	59
DBG_LB_STALE_CT	60
DBG_INHERIT_IDENTITY	61
DBG_SK_LOOKUP4	62
DBG_SK_LOOKUP6	63
DBG_SK_ASSIGN	64
DBG_L7_LB	65
DBG_SKIP_POLICY	66

DropReason

These values are shared with pkg/monitor/api/drop.go and bpf/lib/common.h. Note that non-drop reasons (i.e. values less than api.DropMin) are not used here.

Name	Number	Description
DROP_REASON_UNKNOWN	0	non-drop reasons
INVALID_SOURCE_MAC	130	drop reasons
INVALID_DESTINATION_MAC	131
INVALID_SOURCE_IP	132
POLICY_DENIED	133
INVALID_PACKET_DROPPED	134
CT_TRUNCATED_OR_INVALID_HEADER	135
CT_MISSING_TCP_ACK_FLAG	136
CT_UNKNOWN_L4_PROTOCOL	137
CT_CANNOT_CREATE_ENTRY_FROM_PACKET	138
UNSUPPORTED_L3_PROTOCOL	139
MISSED_TAIL_CALL	140
ERROR_WRITING_TO_PACKET	141
UNKNOWN_L4_PROTOCOL	142
UNKNOWN_ICMPV4_CODE	143
UNKNOWN_ICMPV4_TYPE	144
UNKNOWN_ICMPV6_CODE	145
UNKNOWN_ICMPV6_TYPE	146
ERROR_RETRIEVING_TUNNEL_KEY	147
ERROR_RETRIEVING_TUNNEL_OPTIONS	148
INVALID_GENEVE_OPTION	149
UNKNOWN_L3_TARGET_ADDRESS	150
STALE_OR_UNROUTABLE_IP	151
NO_MATCHING_LOCAL_CONTAINER_FOUND	152
ERROR_WHILE_CORRECTING_L3_CHECKSUM	153
ERROR_WHILE_CORRECTING_L4_CHECKSUM	154
CT_MAP_INSERTION_FAILED	155
INVALID_IPV6_EXTENSION_HEADER	156
IP_FRAGMENTATION_NOT_SUPPORTED	157
SERVICE_BACKEND_NOT_FOUND	158
NO_TUNNEL_OR_ENCAPSULATION_ENDPOINT	160
FAILED_TO_INSERT_INTO_PROXYMAP	161
REACHED_EDT_RATE_LIMITING_DROP_HORIZON	162
UNKNOWN_CONNECTION_TRACKING_STATE	163
LOCAL_HOST_IS_UNREACHABLE	164
NO_CONFIGURATION_AVAILABLE_TO_PERFORM_POLICY_DECISION	165
UNSUPPORTED_L2_PROTOCOL	166
NO_MAPPING_FOR_NAT_MASQUERADE	167
UNSUPPORTED_PROTOCOL_FOR_NAT_MASQUERADE	168
FIB_LOOKUP_FAILED	169
ENCAPSULATION_TRAFFIC_IS_PROHIBITED	170
INVALID_IDENTITY	171
UNKNOWN_SENDER	172
NAT_NOT_NEEDED	173
IS_A_CLUSTERIP	174
FIRST_LOGICAL_DATAGRAM_FRAGMENT_NOT_FOUND	175
FORBIDDEN_ICMPV6_MESSAGE	176
DENIED_BY_LB_SRC_RANGE_CHECK	177
SOCKET_LOOKUP_FAILED	178
SOCKET_ASSIGN_FAILED	179
PROXY_REDIRECTION_NOT_SUPPORTED_FOR_PROTOCOL	180
POLICY_DENY	181
VLAN_FILTERED	182
INVALID_VNI	183
INVALID_TC_BUFFER	184
NO_SID	185
MISSING_SRV6_STATE	186
NAT46	187
NAT64	188
AUTH_REQUIRED	189
CT_NO_MAP_FOUND	190
SNAT_NO_MAP_FOUND	191
INVALID_CLUSTER_ID	192
UNSUPPORTED_PROTOCOL_FOR_DSR_ENCAP	193
NO_EGRESS_GATEWAY	194
UNENCRYPTED_TRAFFIC	195
TTL_EXCEEDED	196
NO_NODE_ID	197
DROP_RATE_LIMITED	198
DROP_HOST_NOT_READY	202	A BPF program wants to tail call into bpf_host, but the host datapath hasn't been loaded yet.

EventType

EventType are constants are based on the ones from <linux/perf_event.h>.

Name	Number	Description
UNKNOWN	0
EventSample	9	EventSample is equivalent to PERF_RECORD_SAMPLE.
RecordLost	2	RecordLost is equivalent to PERF_RECORD_LOST.

FlowType

Name	Number	Description
UNKNOWN_TYPE	0
L3_L4	1	not sure about the underscore here, but L34 also reads strange
L7	2
SOCK	3

IPVersion

Name	Number	Description
IP_NOT_USED	0
IPv4	1
IPv6	2

L7FlowType

This enum corresponds to Cilium's L7 accesslog FlowType:

Name	Number	Description
UNKNOWN_L7_TYPE	0
REQUEST	1
RESPONSE	2
SAMPLE	3

LostEventSource

Name	Number	Description
UNKNOWN_LOST_EVENT_SOURCE	0
PERF_EVENT_RING_BUFFER	1	PERF_EVENT_RING_BUFFER indicates that events were dropped in the BPF perf event ring buffer, indicating that userspace agent did not keep up with the events produced by the datapath.
OBSERVER_EVENTS_QUEUE	2	OBSERVER_EVENTS_QUEUE indicates that events were dropped because the Hubble events queue was full, indicating that the Hubble observer did not keep up.
HUBBLE_RING_BUFFER	3	HUBBLE_RING_BUFFER indicates that the event was dropped because it could not be read from Hubble's ring buffer in time before being overwritten.

SocketTranslationPoint

This mirrors enum xlate_point in bpf/lib/trace_sock.h

Name	Number	Description
SOCK_XLATE_POINT_UNKNOWN	0
SOCK_XLATE_POINT_PRE_DIRECTION_FWD	1	Pre service translation
SOCK_XLATE_POINT_POST_DIRECTION_FWD	2	Post service translation
SOCK_XLATE_POINT_PRE_DIRECTION_REV	3	Pre reverse service translation
SOCK_XLATE_POINT_POST_DIRECTION_REV	4	Post reverse service translation

TraceObservationPoint

Name	Number	Description
UNKNOWN_POINT	0	Cilium treats 0 as TO_LXC, but its's something we should work to remove. This is intentionally set as unknown, so proto API can guarantee the observation point is always going to be present on trace events.
TO_PROXY	1	TO_PROXY indicates network packets are transmitted towards the l7 proxy.
TO_HOST	2	TO_HOST indicates network packets are transmitted towards the host namespace.
TO_STACK	3	TO_STACK indicates network packets are transmitted towards the Linux kernel network stack on host machine.
TO_OVERLAY	4	TO_OVERLAY indicates network packets are transmitted towards the tunnel device.
TO_ENDPOINT	101	TO_ENDPOINT indicates network packets are transmitted towards endpoints (containers).
FROM_ENDPOINT	5	FROM_ENDPOINT indicates network packets were received from endpoints (containers).
FROM_PROXY	6	FROM_PROXY indicates network packets were received from the l7 proxy.
FROM_HOST	7	FROM_HOST indicates network packets were received from the host namespace.
FROM_STACK	8	FROM_STACK indicates network packets were received from the Linux kernel network stack on host machine.
FROM_OVERLAY	9	FROM_OVERLAY indicates network packets were received from the tunnel device.
FROM_NETWORK	10	FROM_NETWORK indicates network packets were received from native devices.
TO_NETWORK	11	TO_NETWORK indicates network packets are transmitted towards native devices.

TrafficDirection

Name	Number	Description
TRAFFIC_DIRECTION_UNKNOWN	0
INGRESS	1
EGRESS	2

Verdict

Name	Number	Description
VERDICT_UNKNOWN	0	UNKNOWN is used if there is no verdict for this flow event
FORWARDED	1	FORWARDED is used for flow events where the trace point has forwarded this packet or connection to the next processing entity.
DROPPED	2	DROPPED is used for flow events where the connection or packet has been dropped (e.g. due to a malformed packet, it being rejected by a network policy etc). The exact drop reason may be found in drop_reason_desc.
ERROR	3	ERROR is used for flow events where an error occurred during processing
AUDIT	4	AUDIT is used on policy verdict events in policy audit mode, to denominate flows that would have been dropped by policy if audit mode was turned off
REDIRECTED	5	REDIRECTED is used for flow events which have been redirected to the proxy
TRACED	6	TRACED is used for flow events which have been observed at a trace point, but no particular verdict has been reached yet
TRANSLATED	7	TRANSLATED is used for flow events where an address has been translated

Scalar Value Types

.proto Type	Notes	C++	Java	Python	Go	C#	PHP	Ruby
double		double	double	float	float64	double	float	Float
float		float	float	float	float32	float	float	Float
int32	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint32 instead.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
int64	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint64 instead.	int64	long	int/long	int64	long	integer/string	Bignum
uint32	Uses variable-length encoding.	uint32	int	int/long	uint32	uint	integer	Bignum or Fixnum (as required)
uint64	Uses variable-length encoding.	uint64	long	int/long	uint64	ulong	integer/string	Bignum or Fixnum (as required)
sint32	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sint64	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s.	int64	long	int/long	int64	long	integer/string	Bignum
fixed32	Always four bytes. More efficient than uint32 if values are often greater than 2^28.	uint32	int	int	uint32	uint	integer	Bignum or Fixnum (as required)
fixed64	Always eight bytes. More efficient than uint64 if values are often greater than 2^56.	uint64	long	int/long	uint64	ulong	integer/string	Bignum
sfixed32	Always four bytes.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sfixed64	Always eight bytes.	int64	long	int/long	int64	long	integer/string	Bignum
bool		bool	boolean	boolean	bool	bool	boolean	TrueClass/FalseClass
string	A string must always contain UTF-8 encoded or 7-bit ASCII text.	string	String	str/unicode	string	string	string	String (UTF-8)
bytes	May contain any arbitrary sequence of bytes.	string	ByteString	str	[]byte	ByteString	string	String (ASCII-8BIT)