diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/raw/GlobalRealmMigration.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/raw/GlobalRealmMigration.kt
index 091502f2b1..49bcc72181 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/raw/GlobalRealmMigration.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/raw/GlobalRealmMigration.kt
@@ -35,5 +35,7 @@ internal object GlobalRealmMigration : RealmMigration {
     private fun migrateTo1(realm: DynamicRealm) {
         realm.schema.create("KnownServerUrlEntity")
                 .addField(KnownServerUrlEntityFields.URL, String::class.java)
+                .addPrimaryKey(KnownServerUrlEntityFields.URL)
+                .setRequired(KnownServerUrlEntityFields.URL, true)
     }
 }