# Partitions

> RouterOS allows repartitioning NAND flash on compatible devices to enable multiple OS installations with automatic fallback, ensuring system reliability during upgrades. The feature supports up to 8 partitions,...

# Partitions

Partitioning is supported on ARM, ARM64, MIPS, TILE, and PowerPC RouterBOARD devices that use NAND flash.

RouterOS allows repartitioning of NAND flash, enabling:

- Separate RouterOS installations on each partition.
- The ability to specify primary and fallback partitions.

If one partition fails to boot (due to a failed upgrade, configuration issue, or software error), the next partition will automatically boot, providing a fallback. This feature acts as an interactive backup, allowing you to keep a verified, working installation and perform upgrades only on a secondary partition.

Once you've confirmed the new configuration is stable, you can use the "Save Config To" function to copy it to the other partitions.

:::warning
Repartitioning of the NAND requires the latest bootloader version
:::

#### Requirements and Limits

- Starting from RouterOS 7.20beta2, the minimum storage size for repartitioning is 128 MiB.
- Minimum RouterOS partition size during repartitioning: 60 MiB.
- The maximum number of allowed partitions is 8.

For devices where the Partitions menu is supposed to be hidden, but were previously repartitioned:

- It will be possible to repartition into a single partition.

- The Partitions menu will then be hidden after reboot.

#### Example

For a device with 128 MiB NAND that previously had 4\*32 MiB partitions, where RouterOS fits within 32 MiB, the behavior after upgrading, starting from RouterOS 7.20beta2, will be as follows:

- It will continue using all 4 partitions with full partitioning options, as before repartitioning.
- In case of repartitioning, the only available options will be 1\*128 MiB or 2\*64 MiB partitions, and full partitioning features will remain available.

```ros
[admin@MikroTik] > /partitions/print
Flags: A - ACTIVE; R - RUNNING
Columns: NAME, FALLBACK-TO, VERSION, SIZE
# NAME FALL VERSION SIZE 
0 AR part0  next         RouterOS v7.18.2 2025-03-11 11:59:04  128MiB
```

:::warning
Starting from RouterOS version 7.17, you need to update the [device-mode](./device-mode.md) to use the partitions.
:::

## Inspect partitions in WinBox

Open **Partition** in the left menu:

1. Check the partition name, **Fallback To**, and installed RouterOS version in the list. The `A` flag identifies the active boot partition, and `R` identifies the running partition. The screenshot shows one partition, `part0`, with both flags.
2. The right panel contains **Repartition**, **Copy To**, **Save Config To**, and **Restore Config From**. These actions change storage or configuration; use the command descriptions to select the operation you intend to perform.

![WinBox Partition overview with partition details and available actions](./img/partitions-winbox.webp)

Viewing the list does not repartition the router. **Repartition** reformats storage and reboots the device, and **Copy To** replaces the contents of its destination. Check hardware support and device mode before planning a partition change.

## Commands

| Property | Description |
| :-- | :-- |
| **activate** (*partition*) | Assigns another partition as Active. This option is available if the "partitions" setting is enabled in device mode (since RouterOS 7.17). |
| **repartition** (*integer*) | Will reboot the router and reformat the NAND, leaving only the active partition. |
| **copy-to** (*partition*) | Clone the **running** OS with the config to the specified partition. Previously stored data on the partition will be erased. |
| **save-config-to** (*partition*) | Clone **running-config** on a specified partition. Everything else is untouched. |
| **restore-config-from** (*partition*) | Copy config from the specified partition to the **running** partition |

## Properties

| Property | Description |
| :-- | :-- |
| **name** (*string*; Default: ) | Name of the partition |
| **fallback-to** (*etherboot \| next \| partition-name*; Default: **next**) | What to do if an active partition fails to boot:etherboot - switch to etherbootnext - try next partitionfallback to the specified partition |

### Read-only

| Property | Description |
| :-- | :-- |
| **active** (*yes \| no*) | Partition is active |
| **running** (*yes \| no*) | Currently running partition |
| **size** (*integer[MiB]*) | Partition size |
| **version** (*string*) | Current RouterOS version installed on the partition |