New feature: per-VIP / per-backend runtime counters
* New GetVPPLBCounters RPC serving an in-process snapshot refreshed
by a 5s scrape loop (internal/vpp/lbstats.go). Each cycle pulls
the LB plugin's four SimpleCounters (next, first, untracked,
no-server) plus the FIB /net/route/to CombinedCounter for every
VIP and every backend host prefix via a single DumpStats call.
* FIB stats-index discovery via ip_route_lookup (internal/vpp/
fibstats.go); per-worker reduction happens in the collector.
* Prometheus collector exports vip_packets_total (kind label),
vip_route_{packets,bytes}_total, and backend_route_{packets,
bytes}_total. Metrics source interface extended with VIPStats /
BackendRouteStats; vpp.Client publishes snapshots via
atomic.Pointer and clears them on disconnect.
* New 'show vpp lb counters' CLI command. The 'show vpp lbstate'
and 'sync vpp lbstate' commands are restructured under 'show
vpp lb {state,counters}' / 'sync vpp lb state' to make room
for the new verb.
New feature: src-ip-sticky frontends
* New frontend YAML key 'src-ip-sticky' (bool). Plumbed through
config.Frontend, desiredVIP, and the lb_add_del_vip_v2 call.
* Reflected in gRPC FrontendInfo.src_ip_sticky and VPPLBVIP.
src_ip_sticky, and shown in 'show vpp lb state' output.
* Scraped back from VPP by parsing 'show lb vips verbose' through
cli_inband — lb_vip_details does not expose the flag. The same
scrape also recovers the LB pool index for each VIP, which the
stats-segment counters are keyed on. This is a documented
temporary workaround until VPP ships an lb_vip_v2_dump.
* src_ip_sticky cannot be mutated on a live VIP, so a flipped flag
triggers a tear-down-and-recreate in reconcileVIP (ASes deleted
with flush, VIP deleted, then re-added). Flip is logged.
New feature: frontend state aggregation and events
* New health.FrontendState (unknown/up/down) and FrontendTransition
types. A frontend is 'up' iff at least one backend has a nonzero
effective weight, 'unknown' iff no backend has real state yet,
and 'down' otherwise.
* Checker tracks per-frontend aggregate state, recomputing after
each backend transition and emitting a frontend-transition Event
on change. Reload drops entries for removed frontends.
* checker.Event gains an optional FrontendTransition pointer;
backend- vs. frontend-transition events are demultiplexed on
that field.
* WatchEvents now sends an initial snapshot of frontend state on
connect (mirroring the existing backend snapshot), subscribes
once to the checker stream, and fans out to backend/frontend
handlers based on the client's filter flags. The proto
FrontendEvent message grows name + transition fields.
* New Checker.FrontendState accessor.
Refactor: pure health helpers
* Moved the priority-failover selector and the (pool idx, active
pool, state, cfg weight) → (vpp weight, flush) mapping out of
internal/vpp/lbsync.go into a new internal/health/weights.go so
the checker can reuse them for frontend-state computation
without importing internal/vpp.
* New functions: health.ActivePoolIndex, BackendEffectiveWeight,
EffectiveWeights, ComputeFrontendState. lbsync.go now calls
these directly; vpp.EffectiveWeights is a thin wrapper over
health.EffectiveWeights retained for the gRPC observability
path. Fully unit-tested in internal/health/weights_test.go.
maglevc polish
* --color default is now mode-aware: on in the interactive shell,
off in one-shot mode so piped output is script-safe. Explicit
--color=true/false still overrides.
* New stripHostMask helper drops /32 and /128 from VIP display;
non-host prefixes pass through unchanged.
* Counter table column order fixed (first before next) and
packets/bytes columns renamed to fib-packets/fib-bytes to
clarify they come from the FIB, not the LB plugin.
Docs
* config-guide: document src-ip-sticky, including the VIP
recreate-on-change caveat.
* user-guide, maglevc.1, maglevd.8: updated command tree, new
counters command, color defaults, and the src-ip-sticky field.
maglevd
Health checker and gRPC control plane for VPP Maglev load balancing.
Build and Install
make # builds build/<arch>/maglevd and build/<arch>/maglevc
make test # runs all tests
make pkg-deb # Creates a debian package for arm64 and amd64
Requires Go 1.25+ and (for make proto) protoc with protoc-gen-go and
protoc-gen-go-grpc.
Produces vpp-maglev_<version>_amd64.deb and vpp-maglev_<version>_arm64.deb
in the build/ directory by cross-compiling with GOOS=linux GOARCH=<arch>.
Requires dpkg-deb (available on any Debian/Ubuntu host).
Running
After installing, the unit is enabled but not started automatically:
# edit /etc/vpp-maglev/maglev.yaml, then:
systemctl enable --now vpp-maglevd
Or run the server and client by hand:
maglevd --config /etc/vpp-maglev/maglev.yaml --grpc-addr :9090
maglevd --version # print version and exit
maglevc --server localhost:9090 # interactive shell
maglevc show frontends # one-shot
maglevc -color=false show backends # one-shot, no ANSI color
maglevc set backend nginx0-ams pause
Send SIGHUP to maglevd to reload config without restarting.
maglevd requires CAP_NET_RAW for ICMP health checks.
Check out a minimal configuration file in [debian/maglev.yaml].
See docs/user-guide.md for flags, signals, and maglevc usage.
See docs/config-guide.md for the full configuration reference.
See docs/healthchecks.md for health state machine details.
Docker
docker build -t maglevd .
docker run --cap-add NET_RAW -v /etc/vpp-maglev:/etc/vpp-maglev maglevd