It is easy to implement RAID1-like replication in VictoriaMetrics: just set up independent VictoriaMetrics instances (single-node or clusters) and replicate all the incoming data simultaneously to these instances. This can be done either via providing multiple `remote_write->url` values in Prometheus configs or via providing multiple `-remoteWrite.url` command-line flags in vmagent [1]. Then query multiple VictoriaMetrics replicas via Promxy [2].

[1] https://github.com/VictoriaMetrics/VictoriaMetrics/blob/mast...

[2] https://github.com/jacksontj/promxy