> For the complete documentation index, see [llms.txt](https://mariadb.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mariadb.com/docs/gridgain/gridgain-8/gridgain8-management/migration-guides/gridgain-8-9-to-8-10/configuration-and-defaults.md). # Configuration and Default Value Changes Configuration changes when upgrading from GridGain 8.9 to 8.10: the SFTP host key default, vector search limits, startup messages, JMX metric types, and system properties. GridGain 8.10 changes the SFTP host key default and adds vector search limits. It also changes startup messages, JMX metric types, and system properties. ## SFTP Snapshot Transport Verifies the Host Key by Default `SftpConfiguration.strictHostKeyChecking` now defaults to `true`. In 8.9.x it defaulted to `false`. Before the first snapshot transfer to an SFTP destination, add the server to the OpenSSH-format known hosts file, or set `strictHostKeyChecking` to `false`. Otherwise transfers fail. The file is the one that `knownHostsPath` points at. If `knownHostsPath` is not set, the file is `~/.ssh/known_hosts` of the account that runs the node. For more information, see [Configuring SFTP Location](/docs/gridgain/gridgain-8/gridgain8-management/backup-and-replication/snapshots/network-backups.md#configuring-sftp-location). ## Vector Search Limits Vector search now enforces limits and rejects queries above them: * The number of dimensions of a vector index is limited by `GRIDGAIN_VECTOR_MAX_DIMENSIONS`, which defaults to 4096. A vector with 4097 or more dimensions is rejected when you put it into the cache (`Field [VEC_VEC] vector's dimensions must be <= [4096]`). The limit applies to indexes that are created after the property is set, so raise it before you create indexes on wider vectors. Memory use and search time grow with the number of dimensions. * A vector query may request at most `GRIDGAIN_VECTOR_MAX_K` neighbors (default 10000). A query with `k` below 1 or above the limit is rejected with a `CacheException`, for example `Vector query 'k' is above the maximum number of neighbors a query may ask for [k=10001, max=10000]`. The limit is read in the JVM that runs the query, so set the property on the application that runs queries as a thick client, and on the server nodes for thin-client queries. Neither limit exists in 8.9.x. A vector index that you built on 8.9 needs no migration. The index is kept in memory and rebuilt from the cache data each time a node starts, so a node that you upgrade opens the existing data and returns the same results. For more information, see [Vector Search](/docs/gridgain/gridgain-8/gridgain8-development/accessing-data/vector-search.md). ## Startup Messages for Stale Properties This section applies if your configuration or startup scripts set unsupported Apache Ignite properties. An unknown property in the Spring XML configuration still fails node startup, as it did in 8.9.x, but the message is now short and names the bean and the property, for example `Configuration property IgniteConfiguration.noSuchProperty does not exist`. GridGain 8.10 also logs a warning at node start for each Apache Ignite system property or environment variable in the following table. Only these exact names are checked, and the list is fixed. The warning names the property and the reason, and links to the Apache Ignite migration guide. The node starts normally. Remove these properties from your startup scripts. | Property | Reason | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------ | | `IGNITE_CALCITE_EXEC_IN_BUFFER_SIZE`, `IGNITE_CALCITE_EXEC_IO_BATCH_CNT`, `IGNITE_CALCITE_EXEC_IO_BATCH_SIZE`, `IGNITE_CALCITE_EXEC_MODIFY_BATCH_SIZE`, `IGNITE_CALCITE_REL_JSON_PRETTY_PRINT` | The GridGain SQL engine is H2-based. The Calcite engine is not available. | | `IGNITE_SNAPSHOT_SEQUENTIAL_WRITE` | The GridGain snapshot subsystem differs from Apache Ignite. | | `IGNITE_PERF_STAT_BUFFER_SIZE`, `IGNITE_PERF_STAT_CACHED_STRINGS_THRESHOLD`, `IGNITE_PERF_STAT_FILE_MAX_SIZE`, `IGNITE_PERF_STAT_FLUSH_SIZE` | The performance statistics subsystem is not implemented. Use GridGain metrics. | | `IGNITE_ALLOW_MIXED_CACHE_GROUPS` | Mixed cache groups are not available. | | `IGNITE_ENABLE_OBJECT_INPUT_FILTER_AUTOCONFIGURATION` | Object input filter auto-configuration is not available. | | `IGNITE_USE_BINARY_ARRAYS` | Typed binary arrays are not available. | | `IGNITE_SQL_FORCE_LAZY_RESULT_SET` | Not available in the H2-based SQL engine. | ## JMX Object Metrics Are Strings Metric values of the `ObjectMetric` type are exposed through JMX as strings. A JMX tool that reads these attributes gets a `String` instead of the typed object. For example, in the `ignite` metric registry, `localNodeId` was a `UUID` in 8.9.x and is a `String` in 8.10. The same applies to `userAttributesFormatted`, `lifecycleBeansFormatted`, and `longJVMPauseLastEvents`. {% hint style="info" %} The metric MBeans exist only if you configure `JmxMetricExporterSpi` in `IgniteConfiguration.metricExporterSpi`. The default exporter does nothing. {% endhint %} ## System Properties The following system properties are new or removed in 8.10: | Property | Change | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `IGNITE_REST_SCAN_QUERY_FILTER_CLASSES` | New. See [REST Scan Queries With a Filter Class](/docs/gridgain/gridgain-8/gridgain8-management/migration-guides/gridgain-8-9-to-8-10/security-and-licensing.md#rest-scan-queries-with-a-filter-class). | | `GRIDGAIN_VECTOR_MAX_DIMENSIONS`, `GRIDGAIN_VECTOR_MAX_K` | New. See [Vector Search Limits](#vector-search-limits). | | `GRIDGAIN_VECTOR_BINARY_QUANTIZATION`, `GRIDGAIN_VECTOR_INDEX_DELETES_PCT`, `GRIDGAIN_VECTOR_INDEX_MAX_SEGMENTS`, `GRIDGAIN_VECTOR_INDEX_RAM_BUFFER_MB`, `GRIDGAIN_VECTOR_NOCOPY_SCORER`, `GRIDGAIN_VECTOR_QUERY_CACHE_MIN_SEGMENT_DOCS`, `GRIDGAIN_VECTOR_QUERY_CACHE_MIN_SEGMENT_SIZE_RATIO`, `GRIDGAIN_VECTOR_QUERY_THREADS` | New. Vector index and query tuning. No action is needed. `GRIDGAIN_VECTOR_BINARY_QUANTIZATION` is `false` by default. See [Vector Search](/docs/gridgain/gridgain-8/gridgain8-development/accessing-data/vector-search.md). | | `IGNITE_CUSTOM_METRICS_MAX_NAME_LENGTH` | New. Limits the length of custom metric registry and metric names. The default is 256. | | `IGNITE_TCP_COMM_MSG_QUEUE_WARN_SIZE` | New. When set to a positive number, logs a warning when the outgoing message queue of the TCP communication SPI exceeds it. The default is 0, which prints no warning. | | `IGNITE_BPLUS_TREE_DISABLE_METRICS` | New. Disables the metrics of the secondary index B+Trees. The default is `false`. | | `IGNITE_LOCAL_STORE_KEEPS_PRIMARY_ONLY` | Removed with local store support. See [Local Store Support Removed](/docs/gridgain/gridgain-8/gridgain8-management/migration-guides/gridgain-8-9-to-8-10/platform-and-modules.md#local-store-support-removed). |