diff --git a/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/service/MigrationConfig.java b/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/service/MigrationConfig.java
index 33f7f32..16fb672 100644
--- a/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/service/MigrationConfig.java
+++ b/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/service/MigrationConfig.java
@@ -41,6 +41,10 @@
     public static final String NUMBER_OF_REPLICAS = "number_of_replicas";
     public static final String TOTAL_FIELDS_LIMIT = "mapping.total_fields.limit";
     public static final String MAX_DOC_VALUE_FIELDS_SEARCH = "max_docvalue_fields_search";
+    public static final String MONTHLY_NUMBER_OF_SHARDS = "monthlyIndex." + NUMBER_OF_SHARDS;
+    public static final String MONTHLY_NUMBER_OF_REPLICAS = "monthlyIndex." + NUMBER_OF_REPLICAS;
+    public static final String MONTHLY_TOTAL_FIELDS_LIMIT = "monthlyIndex." + TOTAL_FIELDS_LIMIT;
+    public static final String MONTHLY_MAX_DOC_VALUE_FIELDS_SEARCH = "monthlyIndex." + MAX_DOC_VALUE_FIELDS_SEARCH;
     public static final String MIGRATION_HISTORY_RECOVER = "recoverFromHistory";
 
     protected static final Map<String, MigrationConfigProperty> configProperties;
@@ -52,10 +56,14 @@
         m.put(CONFIG_ES_PASSWORD, new MigrationConfigProperty("Enter ElasticSearch TARGET password (default: none): ", ""));
         m.put(CONFIG_TRUST_ALL_CERTIFICATES, new MigrationConfigProperty("We need to initialize a HttpClient, do we need to trust all certificates ? (yes/no)", null));
         m.put(INDEX_PREFIX, new MigrationConfigProperty("Enter ElasticSearch Unomi indices prefix (default: context): ", "context"));
-        m.put(NUMBER_OF_SHARDS, new MigrationConfigProperty("Enter ElasticSearch index mapping configuration: number_of_shards (default: 3): ", "3"));
+        m.put(NUMBER_OF_SHARDS, new MigrationConfigProperty("Enter ElasticSearch index mapping configuration: number_of_shards (default: 5): ", "5"));
         m.put(NUMBER_OF_REPLICAS, new MigrationConfigProperty("Enter ElasticSearch index mapping configuration: number_of_replicas (default: 0): ", "0"));
         m.put(TOTAL_FIELDS_LIMIT, new MigrationConfigProperty("Enter ElasticSearch index mapping configuration: mapping.total_fields.limit (default: 1000): ", "1000"));
         m.put(MAX_DOC_VALUE_FIELDS_SEARCH, new MigrationConfigProperty("Enter ElasticSearch index mapping configuration: max_docvalue_fields_search (default: 1000): ", "1000"));
+        m.put(MONTHLY_NUMBER_OF_SHARDS, new MigrationConfigProperty("Enter ElasticSearch monthly index (event, session) mapping configuration: number_of_shards (default: 5): ", "5"));
+        m.put(MONTHLY_NUMBER_OF_REPLICAS, new MigrationConfigProperty("Enter ElasticSearch monthly index (event, session) mapping configuration: number_of_replicas (default: 0): ", "0"));
+        m.put(MONTHLY_TOTAL_FIELDS_LIMIT, new MigrationConfigProperty("Enter ElasticSearch monthly index (event, session) mapping configuration: mapping.total_fields.limit (default: 1000): ", "1000"));
+        m.put(MONTHLY_MAX_DOC_VALUE_FIELDS_SEARCH, new MigrationConfigProperty("Enter ElasticSearch monthly index (event, session) mapping configuration: max_docvalue_fields_search (default: 1000): ", "1000"));
         m.put(MIGRATION_HISTORY_RECOVER, new MigrationConfigProperty("We found an existing migration attempt, should we restart from it ? (this will avoid redoing steps already completed successfully) (yes/no)", null));
         configProperties = Collections.unmodifiableMap(m);
     }
diff --git a/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/utils/MigrationUtils.java b/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/utils/MigrationUtils.java
index d44be38..a57d79d 100644
--- a/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/utils/MigrationUtils.java
+++ b/tools/shell-commands/src/main/java/org/apache/unomi/shell/migration/utils/MigrationUtils.java
@@ -41,6 +41,8 @@
 import java.util.Set;
 import java.util.stream.Collectors;
 
+import static org.apache.unomi.shell.migration.service.MigrationConfig.*;
+
 /**
  * @author dgaillard
  */
@@ -123,20 +125,12 @@
         throw new RuntimeException("no mapping found in bundles for: " + fileName);
     }
 
-    public static String buildIndexCreationRequest(CloseableHttpClient httpClient, String esAddress, String baseIndexSettings,
-                                            String originalIndexForSettingsExtraction, String mapping) throws IOException {
-
-        String settings = baseIndexSettings;
-
-        // Extract existing settings on index that still exists
-        if (originalIndexForSettingsExtraction != null) {
-            JSONObject originalIndexSettings = new JSONObject(HttpUtils.executeGetRequest(httpClient, esAddress + "/" + originalIndexForSettingsExtraction + "/_settings", null));
-            settings = settings
-                    .replace("#numberOfShards", originalIndexSettings.getJSONObject(originalIndexForSettingsExtraction).getJSONObject("settings").getJSONObject("index").getString("number_of_shards"))
-                    .replace("#numberOfReplicas", originalIndexSettings.getJSONObject(originalIndexForSettingsExtraction).getJSONObject("settings").getJSONObject("index").getString("number_of_replicas"))
-                    .replace("#maxDocValueFieldsSearch", originalIndexSettings.getJSONObject(originalIndexForSettingsExtraction).getJSONObject("settings").getJSONObject("index").getString("max_docvalue_fields_search"))
-                    .replace("#mappingTotalFieldsLimit", originalIndexSettings.getJSONObject(originalIndexForSettingsExtraction).getJSONObject("settings").getJSONObject("index").getJSONObject("mapping").getJSONObject("total_fields").getString("limit"));
-        }
+    public static String buildIndexCreationRequest(String baseIndexSettings, String mapping,  MigrationContext context, boolean isMonthlyIndex) throws IOException {
+        String settings = baseIndexSettings
+                .replace("#numberOfShards", context.getConfigString(isMonthlyIndex ? MONTHLY_NUMBER_OF_SHARDS : NUMBER_OF_SHARDS))
+                .replace("#numberOfReplicas", context.getConfigString(isMonthlyIndex ? MONTHLY_NUMBER_OF_REPLICAS : NUMBER_OF_REPLICAS))
+                .replace("#maxDocValueFieldsSearch", context.getConfigString(isMonthlyIndex ? MONTHLY_MAX_DOC_VALUE_FIELDS_SEARCH : MAX_DOC_VALUE_FIELDS_SEARCH))
+                .replace("#mappingTotalFieldsLimit", context.getConfigString(isMonthlyIndex ? MONTHLY_TOTAL_FIELDS_LIMIT : TOTAL_FIELDS_LIMIT));
 
         return settings.replace("#mappings", mapping);
     }
diff --git a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-01-aliases.groovy b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-01-aliases.groovy
index dcc2a05..685d442 100644
--- a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-01-aliases.groovy
+++ b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-01-aliases.groovy
@@ -1,4 +1,5 @@
 import groovy.json.JsonSlurper
+import org.apache.unomi.shell.migration.service.MigrationConfig
 import org.apache.unomi.shell.migration.service.MigrationContext
 import org.apache.unomi.shell.migration.utils.HttpRequestException
 import org.apache.unomi.shell.migration.utils.HttpUtils
@@ -36,7 +37,7 @@
     if (!MigrationUtils.indexExists(context.getHttpClient(), esAddress, aliasIndex)) {
         String baseRequest = MigrationUtils.resourceAsString(bundleContext,"requestBody/2.0.0/base_index_mapping.json")
         String mapping = MigrationUtils.extractMappingFromBundles(bundleContext, "profileAlias.json")
-        String newIndexSettings = MigrationUtils.buildIndexCreationRequest(context.getHttpClient(), esAddress, baseRequest, profileIndex, mapping)
+        String newIndexSettings = MigrationUtils.buildIndexCreationRequest(baseRequest, mapping, context, false)
         HttpUtils.executePutRequest(context.getHttpClient(), esAddress + "/" + aliasIndex, newIndexSettings, null)
     }
 })
diff --git a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-02-scopes.groovy b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-02-scopes.groovy
index 3f46f0d..d9aa5f8 100644
--- a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-02-scopes.groovy
+++ b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-02-scopes.groovy
@@ -33,7 +33,7 @@
     if (!MigrationUtils.indexExists(context.getHttpClient(), esAddress, scopeIndex)) {
         String baseRequest = MigrationUtils.resourceAsString(bundleContext, "requestBody/2.0.0/base_index_mapping.json")
         String mapping = MigrationUtils.extractMappingFromBundles(bundleContext, "scope.json")
-        String newIndexSettings = MigrationUtils.buildIndexCreationRequest(context.getHttpClient(), esAddress, baseRequest, "${indexPrefix}-profile", mapping)
+        String newIndexSettings = MigrationUtils.buildIndexCreationRequest(baseRequest, mapping, context, false)
         HttpUtils.executePutRequest(context.getHttpClient(), esAddress + "/" + scopeIndex, newIndexSettings, null)
     }
 })
diff --git a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-05-globalReindex.groovy b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-05-globalReindex.groovy
index 826243a..dd841ff 100644
--- a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-05-globalReindex.groovy
+++ b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-05-globalReindex.groovy
@@ -26,6 +26,6 @@
 String[] indicesToReindex = ["segment", "scoring", "campaign", "conditionType", "goal", "patch", "rule"];
 indicesToReindex.each { indexToReindex ->
     String mapping = MigrationUtils.extractMappingFromBundles(bundleContext, "${indexToReindex}.json")
-    String newIndexSettings = MigrationUtils.buildIndexCreationRequest(context.getHttpClient(), esAddress, baseSettings, "${indexPrefix}-profile", mapping)
+    String newIndexSettings = MigrationUtils.buildIndexCreationRequest(baseSettings, mapping, context, false)
     MigrationUtils.reIndex(context.getHttpClient(), bundleContext, esAddress, "${indexPrefix}-${indexToReindex.toLowerCase()}", newIndexSettings, null, context)
 }
diff --git a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-10-profileReindex.groovy b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-10-profileReindex.groovy
index 4711056..bcb4e6a 100644
--- a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-10-profileReindex.groovy
+++ b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-10-profileReindex.groovy
@@ -24,6 +24,6 @@
 
 String baseSettings = MigrationUtils.resourceAsString(bundleContext, "requestBody/2.0.0/base_index_mapping.json")
 String mapping = MigrationUtils.extractMappingFromBundles(bundleContext, "profile.json")
-String newIndexSettings = MigrationUtils.buildIndexCreationRequest(context.getHttpClient(), esAddress, baseSettings, "${indexPrefix}-segment", mapping)
+String newIndexSettings = MigrationUtils.buildIndexCreationRequest(baseSettings, mapping, context, false)
 MigrationUtils.reIndex(context.getHttpClient(), bundleContext, esAddress, indexPrefix + "-profile",
         newIndexSettings, MigrationUtils.getFileWithoutComments(bundleContext, "requestBody/2.0.0/profile_migrate.painless"), context)
diff --git a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-15-eventsReindex.groovy b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-15-eventsReindex.groovy
index 941ff82..a9dc7ae 100644
--- a/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-15-eventsReindex.groovy
+++ b/tools/shell-commands/src/main/resources/META-INF/cxs/migration/migrate-2.0.0-15-eventsReindex.groovy
@@ -32,10 +32,8 @@
 String baseSettings = MigrationUtils.resourceAsString(bundleContext, "requestBody/2.0.0/base_index_mapping.json")
 String reIndexScript = MigrationUtils.getFileWithoutComments(bundleContext, "requestBody/2.0.0/event_migrate.painless");
 String mapping = MigrationUtils.extractMappingFromBundles(bundleContext, "event.json")
+String newIndexSettings = MigrationUtils.buildIndexCreationRequest(baseSettings, mapping, context, true)
 Set<String> eventIndices = MigrationUtils.getIndexesPrefixedBy(context.getHttpClient(), esAddress, "${indexPrefix}-event-")
-// use session indices to extract monthly index settings
-Set<String> sessionIndices = MigrationUtils.getIndexesPrefixedBy(context.getHttpClient(), esAddress, "${indexPrefix}-session-")
-String newIndexSettings = MigrationUtils.buildIndexCreationRequest(context.getHttpClient(), esAddress, baseSettings, sessionIndices[0], mapping)
 eventIndices.each { eventIndex ->
     MigrationUtils.reIndex(context.getHttpClient(), bundleContext, esAddress, eventIndex, newIndexSettings, reIndexScript, context)
 }
\ No newline at end of file
diff --git a/tools/shell-commands/src/main/resources/org.apache.unomi.migration.cfg b/tools/shell-commands/src/main/resources/org.apache.unomi.migration.cfg
index 5749e4c..f4cd527 100644
--- a/tools/shell-commands/src/main/resources/org.apache.unomi.migration.cfg
+++ b/tools/shell-commands/src/main/resources/org.apache.unomi.migration.cfg
@@ -24,6 +24,14 @@
 esPassword = ${org.apache.unomi.elasticsearch.password:-}
 httpClient.trustAllCertificates = ${org.apache.unomi.elasticsearch.sslTrustAllCertificates:-false}
 indexPrefix = ${org.apache.unomi.elasticsearch.index.prefix:-context}
+monthlyIndex.number_of_shards=${org.apache.unomi.elasticsearch.monthlyIndex.nbShards:-5}
+monthlyIndex.number_of_replicas=${org.apache.unomi.elasticsearch.monthlyIndex.nbReplicas:-0}
+monthlyIndex.mapping.total_fields.limit=${org.apache.unomi.elasticsearch.monthlyIndex.indexMappingTotalFieldsLimit:-1000}
+monthlyIndex.max_docvalue_fields_search=${org.apache.unomi.elasticsearch.monthlyIndex.indexMaxDocValueFieldsSearch:-1000}
+number_of_shards=${org.apache.unomi.elasticsearch.defaultIndex.nbShards:-5}
+number_of_replicas=${org.apache.unomi.elasticsearch.defaultIndex.nbReplicas:-0}
+mapping.total_fields.limit=${org.apache.unomi.elasticsearch.defaultIndex.indexMappingTotalFieldsLimit:-1000}
+max_docvalue_fields_search=${org.apache.unomi.elasticsearch.defaultIndex.indexMaxDocValueFieldsSearch:-1000}
 
 # Should the migration try to recover from a previous run ?
 # (This allow to avoid redoing all the steps that would already succeeded on a previous attempt, that was stop or failed in the middle)