| Environment Variable Name | Description | Values |
|---|---|---|
| FLAGCX_IB_HCA | Specifies the type of InfiniBand HCA (Host Channel Adapter) device to use. Used for selecting which RDMA-capable network card/driver FlagCX should bind to | Define to filter IB Verbs interfaces to be used by FlagCX . The list is comma-separated; port numbers can be specified using the : symbol. An optional prefix ^ indicates the list is an exclude list. A second optional prefix = indicates that the tokens are exact names, otherwise by default FlagCX would treat each token as a prefixExamples: :mlx5 — Use all ports of all cards starting with mlx5 =mlx5_0:1,mlx5_1:1 — Use ports 1 of cards mlx5_0 and mlx5_1 ^=mlx5_1,mlx5_4 — Do not use cards mlx5_1 and mlx5_4.Note : using mlx5_1 without a preceding = will select mlx5_1 as well as mlx5_10 to mlx5_19, if they exist. It is therefore always recommended to add the = prefix to ensure an exact match(default) — All available network interfaces are searched |
| FLAGCX_ENABLE_TOPO_DETECT | Specifies whether topology detection is enabled. FlagCX will probe the network topology, bandwidth, and latency between nodes during initialization in order to optimize communication scheduling | TRUE — enable FALSE — disable (default) — FALSE |
| FLAGCX_DEBUG | Specifies whether debug mode is enabled | NONE — no logs VERSION — version info WARN — warning messages INFO — general info ABORT — critical errors, abort TRACE — detailed trace/debug info (default) — NONE |
| FLAGCX_DEBUG_SUBSYS | Specifies which subsystem(s) to enable debug output for | INIT — initialization module COLL — collective operations module NET — network module ENV — environment module PROXY — proxy module BOOTSTRAP — bootstrap module ALL — all subsystems (default) — INIT,ENV |
| FLAGCX_SOCKET_IFNAME | Specifies which network interface FlagCX should bind to and prefer when using socket/TCP-based communication paths | ens102 — bind to interface named ens102 (exact)eth0 — bind to eth0 (exact) or eth prefix to match all eth* interfaceseno1,eno2 — bind to either eno1 or eno2 (list)eth — any interface starting with eth (prefix match)^lo,docker — exclude loopback and docker interfaces (FlagCX-style blacklist) =eth0 — exact-match only for eth0(default) — ^lo,docker |