Files
vpp-maglev/proto/maglev.proto
Pim van Pelt 6b2b04b2d1 Frontend flush-on-down policy; v0.9.3
Adds a per-frontend flush-on-down flag (default true) that causes
maglevd to set is_flush=true on lb_as_set_weight when a backend
transitions to StateDown, tearing down existing flows pinned to
the dead AS instead of just draining them. rise/fall debouncing
in the health checker already absorbs single-probe flaps, so a
fall-counted down is almost always a real outage — and during a
real outage the client-visible "connection refused" oscillation
window (where VPP keeps steering existing flows at a dead AS
until retry) is a reliability regression worth closing by default.
Operators who want the pre-flag drain-only behaviour can set
flush-on-down: false per frontend.

BackendEffectiveWeight's truth table grows one axis: StateDown
now returns (0, flushOnDown); StateDisabled still unconditionally
flushes; StateUnknown / StatePaused still never flush. The unit
test pins all four combinations.

The flag surfaces in the gRPC FrontendInfo message and in
`maglevc show frontend <name>` right next to src-ip-sticky.
2026-04-15 01:43:04 +02:00

310 lines
9.7 KiB
Protocol Buffer

syntax = "proto3";
package maglev;
option go_package = "git.ipng.ch/ipng/vpp-maglev/internal/grpcapi";
// Maglev exposes the state of backend health for all frontends.
service Maglev {
rpc ListFrontends(ListFrontendsRequest) returns (ListFrontendsResponse);
rpc GetFrontend(GetFrontendRequest) returns (FrontendInfo);
rpc ListBackends(ListBackendsRequest) returns (ListBackendsResponse);
rpc GetBackend(GetBackendRequest) returns (BackendInfo);
rpc PauseBackend(BackendRequest) returns (BackendInfo);
rpc ResumeBackend(BackendRequest) returns (BackendInfo);
rpc EnableBackend(BackendRequest) returns (BackendInfo);
rpc DisableBackend(BackendRequest) returns (BackendInfo);
rpc ListHealthChecks(ListHealthChecksRequest) returns (ListHealthChecksResponse);
rpc GetHealthCheck(GetHealthCheckRequest) returns (HealthCheckInfo);
rpc SetFrontendPoolBackendWeight(SetWeightRequest) returns (FrontendInfo);
rpc WatchEvents(WatchRequest) returns (stream Event);
rpc CheckConfig(CheckConfigRequest) returns (CheckConfigResponse);
rpc ReloadConfig(ReloadConfigRequest) returns (ReloadConfigResponse);
rpc GetVPPInfo(GetVPPInfoRequest) returns (VPPInfo);
rpc GetVPPLBState(GetVPPLBStateRequest) returns (VPPLBState);
rpc SyncVPPLBState(SyncVPPLBStateRequest) returns (SyncVPPLBStateResponse);
rpc GetVPPLBCounters(GetVPPLBCountersRequest) returns (VPPLBCounters);
}
// ---- requests ---------------------------------------------------------------
message ListFrontendsRequest {}
message GetFrontendRequest {
string name = 1;
}
message ListBackendsRequest {}
message GetBackendRequest {
string name = 1;
}
message BackendRequest {
string name = 1;
}
message ListHealthChecksRequest {}
message GetHealthCheckRequest {
string name = 1;
}
message CheckConfigRequest {}
message CheckConfigResponse {
bool ok = 1;
string parse_error = 2; // set when YAML cannot be read or parsed
string semantic_error = 3; // set when YAML is valid but semantically incorrect
}
message ReloadConfigRequest {}
message ReloadConfigResponse {
bool ok = 1;
string parse_error = 2; // set when YAML cannot be read or parsed
string semantic_error = 3; // set when YAML is valid but semantically incorrect
string reload_error = 4; // set when config is valid but the reload itself failed
}
message GetVPPInfoRequest {}
message VPPInfo {
string version = 1;
string build_date = 2;
string build_directory = 3;
uint32 pid = 4;
int64 boottime_ns = 5; // unix timestamp (ns) when VPP started (from /sys/boottime)
int64 connecttime_ns = 6; // unix timestamp (ns) when maglevd connected to VPP
}
// ---- VPP load-balancer state ------------------------------------------------
message GetVPPLBStateRequest {}
// VPPLBConf mirrors VPP's lb_conf_get_reply: global LB plugin settings.
message VPPLBConf {
string ip4_src_address = 1;
string ip6_src_address = 2;
uint32 sticky_buckets_per_core = 3;
uint32 flow_timeout = 4;
}
// VPPLBAS is one application server attached to a VIP.
message VPPLBAS {
string address = 1;
uint32 weight = 2; // 0-100
uint32 flags = 3; // VPP AS flags (bit 0 = used, bit 1 = flushed)
uint32 num_buckets = 4;
int64 in_use_since_ns = 5; // unix timestamp (ns), 0 if never used
}
// VPPLBVIP mirrors VPP's lb_vip_details plus the attached application servers.
// Note: srv_type, dscp, and target_port are intentionally omitted — maglevd
// only supports GRE encap, so NAT/L3DSR-specific fields don't apply.
message VPPLBVIP {
string prefix = 1; // CIDR, e.g. 192.0.2.1/32
uint32 protocol = 2; // 6=TCP, 17=UDP, 255=any
uint32 port = 3; // 0 = all-port VIP
string encap = 4; // gre4|gre6|l3dsr|nat4|nat6
uint32 flow_table_length = 5;
repeated VPPLBAS application_servers = 6;
bool src_ip_sticky = 7; // source-IP based sticky session (scraped via cli_inband)
}
message VPPLBState {
VPPLBConf conf = 1;
repeated VPPLBVIP vips = 2;
}
// SyncVPPLBStateRequest triggers a reconciliation between the maglev config
// and the VPP load-balancer dataplane. When frontend_name is set, only that
// frontend's VIP is synced (SyncLBStateVIP) and no VIPs are removed. When
// unset, a full reconciliation runs (SyncLBStateAll), which will also remove
// stale VIPs from VPP.
message SyncVPPLBStateRequest {
optional string frontend_name = 1;
}
message SyncVPPLBStateResponse {}
// ---- VPP load-balancer runtime counters ------------------------------------
// GetVPPLBCountersRequest asks maglevd for the most recent per-VIP and
// per-backend counter snapshot. The data is served from an in-process
// cache that is refreshed every ~5 seconds server-side; the call itself
// is cheap and does not hit VPP.
message GetVPPLBCountersRequest {}
// VPPLBVIPCounters is the point-in-time counter row for a single VIP.
// The four lb_* fields are the LB plugin's SimpleCounters (packets only);
// packets / bytes come from the VPP FIB's combined counter at the VIP's
// host prefix (/net/route/to).
message VPPLBVIPCounters {
string prefix = 1; // CIDR, e.g. 192.0.2.1/32
string protocol = 2; // tcp | udp | any
uint32 port = 3;
uint64 next_packet = 4; // "/packet from existing sessions"
uint64 first_packet = 5; // "/first session packet"
uint64 untracked_packet = 6; // "/untracked packet"
uint64 no_server = 7; // "/no server configured"
uint64 packets = 8; // /net/route/to (FIB, summed across workers)
uint64 bytes = 9; // /net/route/to (FIB, summed across workers)
}
// VPPLBCounters wraps the per-VIP counter list returned by
// GetVPPLBCounters. There is no per-backend counter block: VPP's LB
// plugin forwarding node bypasses ip{4,6}_lookup_inline and writes
// adj_index[VLIB_TX] directly, so /net/route/to at a backend's FIB
// entry never ticks for LB-forwarded traffic — the four per-VIP
// counters are the only per-VIP-and-coarser signal VPP exposes today.
message VPPLBCounters {
repeated VPPLBVIPCounters vips = 1;
// Field 2 (repeated VPPLBBackendCounters backends) was removed; the
// index is reserved so a future replacement doesn't accidentally
// reuse it.
reserved 2;
}
message SetWeightRequest {
string frontend = 1;
string pool = 2;
string backend = 3;
int32 weight = 4; // 0-100
// flush, when true, also clears VPP's flow table for this backend
// so existing sessions are torn down. When false (default), only
// Maglev's new-bucket mapping is updated and live flows keep
// draining to this backend.
bool flush = 5;
}
// WatchRequest controls which event types are streamed. All fields default to
// true (i.e. an empty request subscribes to everything at info level).
message WatchRequest {
optional bool log = 1; // include log events (default: true)
string log_level = 2; // minimum log level: debug|info|warn|error (default: info)
optional bool backend = 3; // include backend transition events (default: true)
optional bool frontend = 4; // include frontend events (default: true)
}
// ---- responses --------------------------------------------------------------
message ListFrontendsResponse {
repeated string frontend_names = 1;
}
message PoolBackendInfo {
string name = 1;
int32 weight = 2; // configured weight from YAML (0-100)
int32 effective_weight = 3; // state-aware weight after pool-failover logic
}
message PoolInfo {
string name = 1;
repeated PoolBackendInfo backends = 2;
}
message FrontendInfo {
string name = 1;
string address = 2;
string protocol = 3;
uint32 port = 4;
repeated PoolInfo pools = 5;
string description = 6;
bool src_ip_sticky = 7; // VPP LB uses src-IP-based stickiness for this VIP
bool flush_on_down = 8; // tear down existing flows when a backend goes down
}
message ListBackendsResponse {
repeated string backend_names = 1;
}
message ListHealthChecksResponse {
repeated string names = 1;
}
message HTTPCheckParams {
string path = 1;
string host = 2;
int32 response_code_min = 3;
int32 response_code_max = 4;
string response_regexp = 5;
string server_name = 6;
bool insecure_skip_verify = 7;
}
message TCPCheckParams {
bool ssl = 1;
string server_name = 2;
bool insecure_skip_verify = 3;
}
message HealthCheckInfo {
string name = 1;
string type = 2;
uint32 port = 3;
string probe_ipv4_src = 4;
string probe_ipv6_src = 5;
int64 interval_ns = 6;
int64 fast_interval_ns = 7;
int64 down_interval_ns = 8;
int64 timeout_ns = 9;
int32 rise = 10;
int32 fall = 11;
HTTPCheckParams http = 12;
TCPCheckParams tcp = 13;
}
message BackendInfo {
string name = 1;
string address = 2;
string state = 3;
repeated TransitionRecord transitions = 4;
bool enabled = 5;
string healthcheck = 6;
}
message TransitionRecord {
string from = 1;
string to = 2;
int64 at_unix_ns = 3;
}
// ---- event stream -----------------------------------------------------------
// LogAttr is a single key/value attribute from a structured log record.
message LogAttr {
string key = 1;
string value = 2;
}
// LogEvent carries a single structured log record.
message LogEvent {
int64 at_unix_ns = 1;
string level = 2;
string msg = 3;
repeated LogAttr attrs = 4;
}
// BackendEvent is emitted on every backend state transition.
message BackendEvent {
string backend_name = 1;
TransitionRecord transition = 2;
}
// FrontendEvent is emitted when a frontend's aggregate state changes.
// Frontends have three states: unknown, up, down. See docs/healthchecks.md.
message FrontendEvent {
string frontend_name = 1;
TransitionRecord transition = 2;
}
// Event is the envelope returned by WatchEvents.
message Event {
oneof event {
LogEvent log = 1;
BackendEvent backend = 2;
FrontendEvent frontend = 3;
}
}