# Enabling Tablets for keyspace after version upgrade, SSTable size limit when importing **URL:** \ **Category:** ScyllaDB\ **Tags:** migration, cql, sstable, upgrade, tablets\ **Created:** [December 18, 2024, 9:13am UTC](https://forum.scylladb.com/t/enabling-tablets-for-keyspace-after-version-upgrade-sstable-size-limit-when-importing/4209 "2024-12-18T09:13:18Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Guy](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.scylladb.com/guy/32/9_2.png) [@Guy](https://forum.scylladb.com/u/Guy)\ **Post date:** [December 18, 2024, 9:13am UTC](https://forum.scylladb.com/t/enabling-tablets-for-keyspace-after-version-upgrade-sstable-size-limit-when-importing/4209/1 "2024-12-18T09:13:18Z")
> [@](#): > > [**Originally from the User Slack**](https://scylladb-users.slack.com/) > > ![Ahmed](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/8/8c77489910df3d18876aa0561e0e72f53f13548f.png) **@Ahmed:** can anyone guide me for enabling tablet for my existing keyspace upgraded from 5 to 6.2 tried sstableloader it’s give unsupported SSTable format or version > > ![avi](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/b5e08becda8d9df1abff1d3a2d9ffe1126ac3fc6.jpeg) **@avi:** It’s not possible to help with such a vague description of the problem > > ![Ahmed](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/8/8c77489910df3d18876aa0561e0e72f53f13548f.png) **@Ahmed:** Hi Avi, > Thanks for your response. Let me clarify: > • I’ve migrated my cluster to version 6.2 from 5.x. > • I have a keyspace with `tablet` disabled, and its size is approximately 3TB. > • My goal is to enable `tablet` for this keyspace. However, as far as I understand, I can’t simply use an `ALTER` command to achieve this. > • I’ve attempted to use `sstableloader` for this migration, but I encountered an issue where it reports “unsupported SSTable format or version.” > I’ve searched for documentation on enabling `tablet` for existing keyspaces post-migration but haven’t found anything relevant. Could you guide me on the proper procedure for enabling `tablet` in this scenario? > Thanks in advance! > > ![avi](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/b5e08becda8d9df1abff1d3a2d9ffe1126ac3fc6.jpeg) **@avi:** First, you need to create an empty keyspace with tablets enabled. > > To migrate data, it’s best to use `nodetool refresh --load-and-stream` , see [https://opensource.docs.scylladb.com/stable/operating-scylla/nodetool-commands/refresh.html](https://opensource.docs.scylladb.com/stable/operating-scylla/nodetool-commands/refresh.html) > > > Nodetool refresh | ScyllaDB Docs > > ![Ahmed](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/8/8c77489910df3d18876aa0561e0e72f53f13548f.png) **@Ahmed:** version 6.2 > enable\_tablets: true in scylla.yaml > `CREATE KEYSPACE IF NOT EXISTS test_new WITH replication = {'class': 'org.apache.cassandra.locator.NetworkTopologyStrategy', 'replication_factor': '2'} AND durable_writes = true AND tablets = {'enabled': true};` > error > `ConfigurationException: Tablet replication is not enabled` > > ![avi](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/b5e08becda8d9df1abff1d3a2d9ffe1126ac3fc6.jpeg) **@avi:** Set `enable_tablets` in scylla.yaml and perform a rolling restart > > ![Ahmed](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/8/8c77489910df3d18876aa0561e0e72f53f13548f.png) **@Ahmed:** Issue with `nodetool refresh` Command > I am encountering an issue when running the following command: > > ```auto > nodetool refresh --load-and-stream main_new table1 > > ``` > > The error message is as follows: > > ```auto > Error executing POST request to with parameters {"load_and_stream": "true", "cf": "table1"}: remote replied with status code 500 Internal Server Error: > Failed to load new sstables: seastar::rpc::stream_closed (rpc stream was closed by peer) > > ``` > > Observations: > > 1. **Incomplete Data Insertion** : > ◦ The error occurs after inserting approximately half of the dataset. > 2. **Dataset Size** : > ◦ The dataset is large, and the issue appears to happen inconsistently at random rows. > 3. **Previous Testing** : > ◦ This similar setup with just 100k rows was tested in a staging environment with no issues. > Request for Help: > I suspect the issue might be related to invalid or corrupt data in the dataset, but the error message provides no details on the problematic row(s). > • How can I pinpoint the source of the issue? > • Is there a way to configure the system to skip invalid rows instead of quitting entirely? > I’d appreciate any guidance or tools that can help debug and resolve this issue, especially for large datasets. > some additional info we copied 56164 files from existing table to new table upload dir now upload dir have only 15434 left. > > ![avi](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/b5e08becda8d9df1abff1d3a2d9ffe1126ac3fc6.jpeg) **@avi:** Check the logs for the actual failure. It’s better to load batches of a smaller number of sstables at a time. > > ![Ahmed](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/2X/8/8c77489910df3d18876aa0561e0e72f53f13548f.png) **@Ahmed:** i tried importing in multiple chunks and it’s worked thanks > I have been encountering a persistent issue where the logs frequently show errors like the following: > `[shard 0:main] storage_proxy - exception during mutation write to 192.168.100.1: std::runtime_error (Key size too large: 70754 > 65535)` > > ![avi](https://us1.discourse-cdn.com/flex016/uploads/scylladb/original/1X/b5e08becda8d9df1abff1d3a2d9ffe1126ac3fc6.jpeg) **@avi:** Keys are limited to 64k. This would usually be caught at the CQL layer. But maybe the sstables you imported contained illegal keys. > > You can use the `scylla sstable dump-data` command to search for these large keys