Multi-tenant Storage Isolation
In this lesson, you will learn how to architect logical partitions that prevent data leakage and ensure strict resource boundaries between multiple users on a single Linux system.
When multiple tenants (users, applications, or virtualized services) share the same physical hardware, the primary risk is "noisy neighbors" or unauthorized data access. Simply creating separate directories isn't enough; we need to use Logical Volume Management (LVM) to create dedicated, isolated containers for each tenant’s data.
Designing Logical Partitions
By using LVM, we treat our physical disks as a flexible pool of storage. We can then carve out specific Logical Volumes (LVs) for each tenant. Because these volumes are managed at the block level, they act as independent disks to the kernel.
Consider a scenario with two tenants, "Alpha" and "Beta." Instead of sharing a partition, we isolate them using separate volumes:
# Create a Volume Group for all tenant data
vgcreate tenant_pool /dev/sdb1
# Allocate a dedicated, isolated volume for Alpha
lvcreate -L 50G -n alpha_storage tenant_pool
# Allocate a dedicated, isolated volume for Beta
lvcreate -L 50G -n beta_storage tenant_pool
Once created, you should format these with individual filesystems and mount them to distinct points (e.g., /mnt/tenants/alpha and /mnt/tenants/beta). By combining these logical volumes with strict ownership permissions (chown) and mount-level restrictions, you ensure that even if one tenant’s service is compromised, they cannot traverse the filesystem to view the blocks belonging to another tenant.
Why Block-Level Isolation Matters
By segregating data into separate volumes, you gain two major benefits:
- Capacity Caps: You can limit each tenant to a specific size, preventing one user from filling up the entire disk and crashing the system for others.
- Metadata Separation: Because the filesystem metadata for each volume is distinct, an error or corruption in one tenant's partition is less likely to propagate to the others.
Key Takeaway: Multi-tenant storage isolation is achieved by mapping individual users to dedicated, size-constrained logical volumes, ensuring that data boundaries are enforced at the block-device layer rather than just the directory level.