After sending the reply, I was thinking… partitionLossPolicy prevents that 
someone tries to modify the DB while a partition is lost (this means that a 
node is not on the cache).

So, if I set partitionLossPolicy = IGNORE the DB can be modified when a node is 
not present.

 

Maybe the solution could be, maintain partitionLossPolicy as READ_WRITE_SAFE 
(all reads and writes will be allowed for keys in valid partitions), and when 
the node rejoins to the cluster, reset the lost partitions.

 

What event do I have to listen? Maybe EVT_NODE_JOINED?

 

From: [email protected] <[email protected]> 
Sent: miércoles, 18 de septiembre de 2024 11:54
To: [email protected]
Subject: RE: Failed to execute query because cache partition has been lost

 

Ok, thanks, I understand.

But in this case, if someone tries to modify the DB while a node is down, does 
Ignites offers any mechanism to prevent this or should I implement it?

 

 

From: Pavel Tupitsyn <[email protected] <mailto:[email protected]> > 
Sent: miércoles, 18 de septiembre de 2024 11:30
To: [email protected] <mailto:[email protected]> 
Subject: Re: Failed to execute query because cache partition has been lost

 

> 2 servers and 1 client, and no backups

> shut down one node

 

There are no backups => any node shutdown leads to partition loss.

If you want to ignore data loss, set partitionLossPolicy = IGNORE [1]

 

[1] 
https://ignite.apache.org/docs/latest/configuring-caches/partition-loss-policy 
<https://www.google.com/url?q=https://ignite.apache.org/docs/latest/configuring-caches/partition-loss-policy&source=gmail-imap&ust=1727256685000000&usg=AOvVaw1bBnb3M95kjNcHsDKBEVir>
 

 

On Wed, Sep 18, 2024 at 12:04 PM <[email protected] <mailto:[email protected]> 
> wrote:

Hi.

 

We are using Apache Ignite in our application, and currently, we are testing 
the behaviour of the system when there are system errors.

 

One of our tests is not working as expected:

*       we have got an Ignite cluster with 2 servers and 1 client, and no 
backups
*       Ignite version 2.16
*       We shut down one node server for several minutes
*       During this time there is no read nor write to Ignite (we do not use 
the DB)
*       When we restart the server node, we expect to recover the system 
smoothly BUT we have exceptions when we query the data: “Failed to execute 
query because cache partition has been lost”

 

We can resolve the problem resetting the lost partitions, but is this a normal 
behaviour of Ignite? I mean, it is a simple case, and the node should be able 
to join the cluster without problems.

 

Thank you.

 

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