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MISCONF Redis is configured to save RDB snapshots, but is currently not able to persist on disk. Commands that may modify the data set are disabled. Please check Redis logs for details about the error. Resque
$ redis-cli
> config set stop-writes-on-bgsave-error no
@abhisheksarka
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I checked the Redis logs which lead me to "Can't save in background: fork: Cannot allocate memory". This in turn lead me to this

Redis background saving schema relies on the copy-on-write semantic of fork in modern operating systems: Redis forks (creates a child process) that is an exact copy of the parent. The child process dumps the DB on disk and finally exits. In theory the child should use as much memory as the parent being a copy, but actually thanks to the copy-on-write semantic implemented by most modern operating systems the parent and child process will share the common memory pages. A page will be duplicated only when it changes in the child or in the parent. Since in theory all the pages may change while the child process is saving, Linux can't tell in advance how much memory the child will take, so if the overcommit_memory setting is set to zero fork will fail unless there is as much free RAM as required to really duplicate all the parent memory pages, with the result that if you have a Redis dataset of 3 GB and just 2 GB of free memory it will fail.

Setting overcommit_memory to 1 says Linux to relax and perform the fork in a more optimistic allocation fashion, and this is indeed what you want for Redis.

@abhisheksarka
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Make sure to set the Linux kernel overcommit memory setting to 1. Add vm.overcommit_memory = 1 to /etc/sysctl.conf and then reboot or run the command sysctl vm.overcommit_memory=1 for this to take effect immediately. https://redis.io/topics/admin

@angeldev20
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Thank you.

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ghost commented Feb 22, 2019

Thanks ( :

@bhavinjr
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Working 👍

@gabmontes
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Thanks!

@iamrexan
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@summerblue when i increase the disk size is again get full .how i can solve this.

@Nleuchter
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Thanks bro

@nasrulhazim
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thanks!

@mikgn
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mikgn commented Dec 19, 2019

Thanks!

@jpcmf
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jpcmf commented Apr 16, 2020

Works!

@Nevillealee
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Still works!

@FernandoBello
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Great ! 👍

@ingemar
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ingemar commented Jun 15, 2020

Thank you!

@jPingua
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jPingua commented Jun 23, 2020

I encountered this issue and my senior was unreachable. I thought I was booked for the day, but this code helped me fix the issue in minutes.

@Barolina
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++++

@alvinyeyint
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Thanks man !

@sailing
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sailing commented May 25, 2021

CONFIG SET dbfilename temp.rdb

This is the way,

What u should be doing is :

# redis-cli
127.0.0.1:6379> CONFIG SET dir /data/tmp
OK
127.0.0.1:6379> CONFIG SET dbfilename temp.rdb
OK
127.0.0.1:6379> BGSAVE
Background saving started
127.0.0.1:6379>

Please Make sure /data/tmp has enough disk space.

this is the way. Thank you for solving the root problem :)

@rajj6
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rajj6 commented Jun 11, 2021

Yep, this happing because current use does not have the permission to modify the "dump.rdb".

So, instead of creating a new RDB file, You can also give permission to old file(change the ownership of it).

In redis-cli enter:

config get dir

you will get "/usr/local/var/db/redis" (this is the location where redis writes the data)

go to this location using terminal

cd 
cd /usr/local/var/db

Type this command(with our username):

sudo chown -R [username] db

This will change to owner.

This works for me.

@a-mellor
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a-mellor commented Jul 7, 2021

Yep, this happing because current use does not have the permission to modify the "dump.rdb".

So, instead of creating a new RDB file, You can also give permission to old file(change the ownership of it).

In redis-cli enter:

config get dir

you will get "/usr/local/var/db/redis" (this is the location where redis writes the data)

go to this location using terminal

cd 
cd /usr/local/var/db

Type this command(with our username):

sudo chown -R [username] db

This will change to owner.

This works for me.

This worked with the addtion of stopping and starting redis

brew services stop redis

brew services start redis

@winhc
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winhc commented Jul 16, 2021

Thanks, that great 👍

@muhiddingithub
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It was helped for me 👍

@minhhungit
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For me, my hard disk is out of space

@AhmedSamyAbdelsalam
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Thanks it's work

@Cibsmart
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Cibsmart commented Mar 2, 2022

Thank you!

@Artorios
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Thanks!

@romain130492
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that's what the command does


  According to Redis documentation, this is recommended only if you don't have RDB snapshots enabled or if you don't care about data persistence in the snapshots.
  
  "By default Redis will stop accepting writes if RDB snapshots are enabled (at least one save point) and the latest background save failed. This will make the user aware (in a hard way) that data is not persisting on disk properly, otherwise,strong text chances are that no one will notice and some disaster will happen."

https://stackoverflow.com/questions/19581059/misconf-redis-is-configured-to-save-rdb-snapshots

@Artorios
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in addition, I want to say that such errors can appear if the radis server is accessible from outside. You need to configure the radis server to listen only localhost. To do this, in the /etc/redis/redis.conf file, change bind parameter to 127.0.0.1
nano /etc/redis/redis.conf
bing 127.0.0.1
After this:
netstat -lnp | grep redis
should show that redis listning 127.0.0.1 insteed 0.0.0.0:*

@Felix-Qi-Wang
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thank you from 2022

@ndimic
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ndimic commented Dec 6, 2022

Thank you!

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