Re: How to add swap file to Azure Linux VM

Ah, forgot to mention, after changing the config file. 

run 

systemctl restart walinuxagent

to make it take effect, you don't need to restart your VM.

feng <fengnz@gmail.com> 于2019年5月7日周二 下午2:23写道：

Login to your VM

Run the following command to edit the config file

[bash]

 sudo vi /etc/waagent.conf

[/bash]  

ResourceDisk.Format=y  

ResourceDisk.EnableSwap=y    

ResourceDisk.SwapSizeMB=4000

I set the swap file to 4000M as my vm only 4000M available

use df -h to check avaialbe disk space on the temp drive /dev/sdb1

[bash]

df -h

Filesystem      Size  Used Avail Use% Mounted on

udev            952M     0  952M   0% /dev

tmpfs           193M  1.2M  192M   1% /run

/dev/sda1        29G  3.1G   26G  11% /

tmpfs           964M  992K  963M   1% /dev/shm

tmpfs           5.0M     0  5.0M   0% /run/lock

tmpfs           964M     0  964M   0% /sys/fs/cgroup

/dev/sda15      105M  3.6M  101M   4% /boot/efi

/dev/sdb1       3.9G  3.9G     0 100% /mnt

tmpfs           193M     0  193M   0% /run/user/1000

/dev/loop0       90M   90M     0 100% /snap/core/6818

/dev/loop1       98M   98M     0 100% /snap/docker/372

[/bash]

Then run free -m to check your new swap file 

[bash]

 free -m

              total        used        free      shared  buff/cache   available

Mem:           1927         930         211           1         786         759

Swap:          3934          16        3917

[/bash]  

use cat /var/log/waagent.log

 to check the log

if you see the following log, means you need to reduce your swap file size as there is no enough space on the temp drive.

[bash]  

2019/05/07 02:10:37.103906 INFO Daemon fallocate unsuccessful, falling back to dd

2019/05/07 02:11:57.305341 INFO Daemon Azure Linux Agent Version:2.2.32.2

2019/05/07 02:11:57.344161 INFO Daemon OS: ubuntu 18.04

2019/05/07 02:11:57.363692 INFO Daemon Python: 3.6.7

2019/05/07 02:11:57.397202 INFO Daemon Add daemon process pid 31642 to walinuxagent systemd cgroup

2019/05/07 02:11:57.425906 INFO Daemon CGroups: ok

2019/05/07 02:11:57.496881 INFO Daemon Run daemon

2019/05/07 02:11:57.507329 INFO Daemon Activate resource disk

2019/05/07 02:11:57.614996 INFO Daemon Resource disk [/dev/sdb1] is already mounted [/mnt]

2019/05/07 02:11:57.642478 WARNING Daemon Failed to write data loss warning:[Errno 1] Operation not permitted: '/mnt/DATALOSS_WARNING_README.txt'

2019/05/07 02:11:57.670093 INFO Daemon Enable swap

2019/05/07 02:11:57.707961 INFO Daemon Remove old swap file

2019/05/07 02:11:58.531786 INFO Daemon Create swap file

2019/05/07 02:11:58.595572 ERROR Daemon Command: [umask 0077 && fallocate -l 4294967296 '/mnt/swapfile'], return code: [1], result: [fallocate: fallocate failed: No space left on device

[/bash]  

--

Feng