Synthetic traffic or sequencer liveness transactions missing
warningreviewed 2026-10-13What it meansmoreTwo synthetic signals check that the L2 includes transactions. The sequencer adds liveness txs to blocks produced more than 8 s after their parent; fewer than 99 % of the blocks that need them carry them over an hour. l2-load sends user transactions and traces them; no user-tx traces for 15 minutes means it stopped or its txs are not mined. INC-07 showed liveness ERROR logs can be noise: the outcome (txs in blocks) is what counts.
ImpactmoreLiveness txs missing: the sequencer's uptime proof on L1 has gaps. No user impact by itself. Load generator stalled: either the generator is down (no impact) or user txs are not included (see l2-node-lagging). Warning; becomes SEV2 if user txs are not included.
Quick mitigation0/4
Check whether the traffic pause is intentional: an implementing CHG (e.g. traffic paused during a catch-up) explains it
Check
l2-load is Running and its last log lines: kubectl -n lineth-l2 logs deploy/l2-load --tail=50If its txs are not mined, check the RPC node has a peer (
l2-node-lagging)Liveness gap with blocks still produced: check the L2 web3signer keys (
l2-signer-keys)Diagnosis3 queries
Share of blocks that needed and carried liveness txs over the last hour:
sum(increase(lineth_l2_liveness_included_blocks_total[1h])) / sum(increase(lineth_l2_liveness_needed_blocks_total[1h]))User-tx traces from l2-load in the last 10 minutes:
sum(increase(traces_spanmetrics_calls_total{source="tempo", network="lineth-local-l2", workflow="user-tx", stage="prepare"}[10m]))l2-load errors:
{namespace="lineth-l2", pod=~"l2-load-.*"} |~ "(?i)not mined|underpriced|nonce|error"Fix0/2
If traffic is paused on purpose, silence this alert for the CHG window rather than letting it fire
If the generator gives up after 3 attempts, make it re-sync its nonce instead of stopping
Escalation
If user transactions sent to the public RPC are not included, treat it as l2-node-lagging and page the IC.
Seen in INC-2026-10-10-07, INC-2026-10-13-13 · SLOs tx-inclusion-5s, tx-inclusion-60s · owner s1ns3nz0