---
name: "daxctl-online-memory"
section: "1"
platform: "linux"
package: "ndctl"
version: "85-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/daxctl-online-memory"
---

# daxctl-online-memory(1)

Online the memory for a device that is in system-ram mode

## NAME

daxctl-online-memory - Online the memory for a device that is in system-ram mode

## SYNOPSIS

```
daxctl online-memory <dax0.0> [<dax1.0>...<daxY.Z>] [<options>]
```

## EXAMPLES

• Reconfigure dax0.0 to system-ram mode, don’t online the memory

```
# daxctl reconfigure-device --mode=system-ram --no-online --human dax0.0
{
  "chardev":"dax0.0",
  "size":"7.87 GiB (8.45 GB)",
  "target_node":2,
  "mode":"system-ram"
}
```

• Online the memory separately

```
# daxctl online-memory dax0.0
dax0.0: 62 new sections onlined
onlined memory for 1 device
```

• Onlining memory when some sections were already online

```
# daxctl online-memory dax0.0
dax0.0: 1 section already online
dax0.0: 61 new sections onlined
onlined memory for 1 device
```

## DESCRIPTION

Online the memory sections associated with a device that has been converted to the system-ram mode. If one or more blocks are already online, print a message about them, and attempt to online the remaining blocks.

This is complementary to the *daxctl-reconfigure-device* command, when used with the *--no-online* option to skip onlining memory sections immediately after the reconfigure. In these scenarios, the memory can be onlined at a later time using *daxctl-online-memory*.

## OPTIONS

\-r, --region=

Restrict the operation to devices belonging to the specified region(s). A device-dax region is a contiguous range of memory that hosts one or more /dev/daxX.Y devices, where X is the region id and Y is the device instance id.

- \--no-movable

  *--movable* is the default. This can be overridden to online new memory such that it is not *movable*. This allows any allocation to potentially be served from this memory. This may preclude subsequent removal. With the *--movable* behavior (which is default), kernel allocations will not consider this memory, and it will be reserved for application use.

- \-u, --human

  By default the command will output machine-friendly raw-integer data. Instead, with this flag, numbers representing storage size will be formatted as human readable strings with units, other fields are converted to hexadecimal strings.

- \-v, --verbose

  Emit more debug messages

## COPYRIGHT

Copyright © 2016 - 2022, Intel Corporation. License GPLv2: GNU GPL version 2  \<http://gnu.org/licenses/gpl.html\>. This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.

## SEE ALSO

[daxctl-reconfigure-device(1)](/daxctl-reconfigure-device/1.md),daxctl-offline-memory\[1\]