gpinitsystem unknown host mdw

I am sure that there are no extra spaces before or after your hostname(S) in the host file, and using ssh mdw can connect to mdw. The /etc/hosts is like this:

 127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
    ::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

The error log:

20161209:21:01:14:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Checking configuration parameters, please wait...
20161209:21:01:14:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Reading Greenplum configuration file /home/gpadmin/gpconfigs/gpinitsystem_config
20161209:21:01:14:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Locale has not been set in /home/gpadmin/gpconfigs/gpinitsystem_config, will set to default value
20161209:21:01:14:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Locale set to en_US.utf8
20161209:21:01:15:030310 gpinitsystem:mdw:gpadmin-[INFO]:-MASTER_MAX_CONNECT not set, will set to default value 250
20161209:21:01:15:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Checking configuration parameters, Completed
20161209:21:01:15:030310 gpinitsystem:mdw:gpadmin-[INFO]:-Commencing multi-home checks, please wait...
.20161209:21:01:17:gpinitsystem:mdw:gpadmin-[FATAL]:-Unknown host mdw Script Exiting!

please.

Answer

How many hosts there are in your greenplum. Your /etc/hosts doesn’t contain any information about mdw and sdw.

Assume you have two hosts named mdw and sdw1 in your greenplum, both of the /etc/hosts files should be like this:

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

172.31.25.24 mdw
172.31.16.170 sdw1

Replace the ip and host name with your own. Before try gpinitsystem again, you’d make sure you have performed gpssh-exkeys succesfully.

UPDATE:

I helped him with this issue using Skype. The answer is that his gpadmin account had no privilege to call ping utility, cause gpinitsystem calls ping to ensure any host in the DBMS exists.