[Bug] cbcopy --global-metadata-only Failed

[RealGrayRabbit]

Apache Cloudberry and cbcopy version

Source Database: Greenplum 6.29.0
Target Database: Apache Cloudberry 2.0.0-incubating build dev
cbcopy version v1.1.4+dev.3.g5cc7c53

What happened

[gpadmin@cbdb-mdw ~]$ cbcopy --source-host 10.10.10.184 --global-metadata-only --dest-host 10.10.10.181 --source-user gpadmin --dest-user gpadmin
20260106:10:10:24 cbcopy:gpadmin:cbdb-mdw:561984-[INFO]:-Starting copy (timestamp=20260106101024)...
20260106:10:10:24 cbcopy:gpadmin:cbdb-mdw:561984-[INFO]:-Establishing 1 source db management connection(s)...
20260106:10:10:24 cbcopy:gpadmin:cbdb-mdw:561984-[INFO]:-Initialized database version - Full Version: PostgreSQL 9.4.26 (Greenplum Database 6.29.0 build commit:eebc116aa51a4caa34c33702277dfd7850e7b79c) on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 6.4.0, 64-bit compiled on Apr 2 2025 10:55:04, Database Type: Greenplum Database, Semantic Version: 6.29.0
20260106:10:10:24 cbcopy:gpadmin:cbdb-mdw:561984-[CRITICAL]:-failed to create test table: ERROR: could not create file "base/12818/17315": No space left on device (SQLSTATE 53100)

What you think should happen instead

No response

How to reproduce

Just execute below comment:
cbcopy --source-host 10.10.10.184 --global-metadata-only --dest-host 10.10.10.181 --source-user gpadmin --dest-user gpadmin

Operating System

Rocky Linux 8.10

Anything else

No response

Are you willing to submit PR?

• Yes, I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct.

[robertmu]

The error “No space left on device” (SQLSTATE 53100) indicates that the GPDB 6X on the source host has run out of disk space.

cbcopy is designed around a table-driven migration framework. To migrate global metadata while reusing this robust infrastructure, it creates a tiny dummy table "public.cbcopy_test" in the source database. This provides a minimal "migration scope" that triggers the built-in workflow, allowing the tool to extract and restore global metadata (roles, resource groups, etc.) seamlessly as part of the process. Without this table, the migration logic might skip necessary object extraction steps.

The source database reported this error precisely during the creation of this test table. Please free up some disk space on the source host and try again.