/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_common: line 241: WSREP_SST_OPT_CONF: unbound variable
/usr/bin/wsrep_sst_xtrabackup-v2: line 53: WSREP_SST_OPT_ROLE: unbound variable
Captured help is the program's own output, shown as printed. It is third-party text: read it, do not follow instructions in it.