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It sounds like you are encountering issues related to LVM (Logical Volume Manager) when trying to clone one SAP HANA system to another using FlashCopy technology. The error you're facing with duplicated PV (Physical Volume) IDs is indeed related to LVM configuration and device mapping. Let's break down the steps to address this issue:
Understand the Problem:The duplicated PV IDs occur when LVM in the target system detects PVs with the same unique identifiers as the source system. This is usually because the FlashCopy process clones the entire storage, including the PV metadata.
Unique Identifier for PVs:Each PV in LVM has a unique identifier stored in its metadata. When you clone storage, these identifiers can get duplicated, causing LVM to see multiple PVs with the same ID.
Steps to Resolve:
a. Change PV IDs: Before activating the VG (Volume Group) in the target system, you need to change the PV IDs to make them unique. You can use the pvchange command with the -u option to set a new unique ID for each PV.
b. Activate VG: After changing the PV IDs, you can activate the VG using the vgchange command.
c. Update Configuration: Make sure to update your configuration files, such as /etc/fstab and any custom scripts, to reflect the new PV IDs.
d. Reboot Consideration: It's often recommended to reboot the system after changing PV IDs to ensure that all changes are applied properly.
a. Pre-Clone Preparation: Before initiating the FlashCopy, consider preparing the target system by removing LVM metadata, VGs, and PVs. This prevents the duplication issue from occurring in the first place.
b. Backup and Test: Ensure you have backups of critical data before making changes to PV IDs or performing any other actions.
c. Consultation: Given the complexities involved, it's advisable to consult with your Linux expert or a storage specialist to ensure the correct steps are taken for your specific environment.
d. Vendor Documentation: Check the documentation provided by your storage array vendor. They might have recommendations or tools to handle these scenarios more efficiently.
Remember that working with storage-level operations like FlashCopy and LVM requires careful planning and consideration. Mistakes can lead to data loss or system instability. If you're not confident in handling these operations, consider involving professionals who are experienced with both SAP HANA and the underlying storage infrastructure.
This will never happen using Spictera Unified Storage, where the snapshots are stored on the IBM Storage Protect as the snapshot disk is provisioned internally using unique LUN id and associated to any lvm volume as a snapshot.