diff --git a/app/replication.py b/app/replication.py
index b9d86ee..994bd7b 100644
--- a/app/replication.py
+++ b/app/replication.py
@@ -66,6 +66,25 @@ class ReplicationManager:
             del self._rules[bucket_name]
             self.save_rules()
 
+    def create_remote_bucket(self, connection_id: str, bucket_name: str) -> None:
+        """Create a bucket on the remote connection."""
+        connection = self.connections.get(connection_id)
+        if not connection:
+            raise ValueError(f"Connection {connection_id} not found")
+
+        try:
+            s3 = boto3.client(
+                "s3",
+                endpoint_url=connection.endpoint_url,
+                aws_access_key_id=connection.access_key,
+                aws_secret_access_key=connection.secret_key,
+                region_name=connection.region,
+            )
+            s3.create_bucket(Bucket=bucket_name)
+        except ClientError as e:
+            logger.error(f"Failed to create remote bucket {bucket_name}: {e}")
+            raise
+
     def trigger_replication(self, bucket_name: str, object_key: str) -> None:
         rule = self.get_rule(bucket_name)
         if not rule or not rule.enabled:
diff --git a/app/s3_api.py b/app/s3_api.py
index 584074b..f9d496f 100644
--- a/app/s3_api.py
+++ b/app/s3_api.py
@@ -8,7 +8,7 @@ import re
 import uuid
 from datetime import datetime, timedelta, timezone
 from typing import Any, Dict
-from urllib.parse import quote, urlencode
+from urllib.parse import quote, urlencode, urlparse
 from xml.etree.ElementTree import Element, SubElement, tostring, fromstring, ParseError
 
 from flask import Blueprint, Response, current_app, jsonify, request
@@ -468,7 +468,17 @@ def _generate_presigned_url(
         "X-Amz-Content-Sha256": "UNSIGNED-PAYLOAD",
     }
     canonical_query = _encode_query_params(query_params)
-    host = request.host
+
+    # Determine host and scheme from config or request
+    api_base = current_app.config.get("API_BASE_URL")
+    if api_base:
+        parsed = urlparse(api_base)
+        host = parsed.netloc
+        scheme = parsed.scheme
+    else:
+        host = request.host
+        scheme = request.scheme or "http"
+
     canonical_headers = f"host:{host}\n"
     canonical_request = "\n".join(
         [
@@ -492,7 +502,6 @@ def _generate_presigned_url(
     signing_key = _derive_signing_key(secret_key, date_stamp, region, service)
     signature = hmac.new(signing_key, string_to_sign.encode(), hashlib.sha256).hexdigest()
     query_with_sig = canonical_query + f"&X-Amz-Signature={signature}"
-    scheme = request.scheme or "http"
     return f"{scheme}://{host}{_canonical_uri(bucket_name, object_key)}?{query_with_sig}"
 
 
diff --git a/app/ui.py b/app/ui.py
index ebc04ca..fbf48a3 100644
--- a/app/ui.py
+++ b/app/ui.py
@@ -1105,6 +1105,16 @@ def update_bucket_replication(bucket_name: str):
         if not target_conn_id or not target_bucket:
             flash("Target connection and bucket are required", "danger")
         else:
+            # Check if user wants to create the remote bucket
+            create_remote = request.form.get("create_remote_bucket") == "on"
+            if create_remote:
+                try:
+                    _replication().create_remote_bucket(target_conn_id, target_bucket)
+                    flash(f"Created remote bucket '{target_bucket}'", "success")
+                except Exception as e:
+                    flash(f"Failed to create remote bucket: {e}", "warning")
+                    # We continue to set the rule even if creation fails (maybe it exists?)
+
             rule = ReplicationRule(
                 bucket_name=bucket_name,
                 target_connection_id=target_conn_id,
diff --git a/templates/bucket_detail.html b/templates/bucket_detail.html
index af93fe8..df6604b 100644
--- a/templates/bucket_detail.html
+++ b/templates/bucket_detail.html
@@ -409,6 +409,7 @@
               </div>
               
               <form method="POST" action="{{ url_for('ui.update_bucket_replication', bucket_name=bucket_name) }}" onsubmit="return confirm('Are you sure you want to disable replication?');">
+                <input type="hidden" name="csrf_token" value="{{ csrf_token() }}" />
                 <input type="hidden" name="action" value="delete">
                 <button type="submit" class="btn btn-danger">Disable Replication</button>
               </form>
@@ -418,6 +419,7 @@
               
               {% if connections %}
               <form method="POST" action="{{ url_for('ui.update_bucket_replication', bucket_name=bucket_name) }}">
+                <input type="hidden" name="csrf_token" value="{{ csrf_token() }}" />
                 <input type="hidden" name="action" value="create">
                 
                 <div class="mb-3">
@@ -434,7 +436,12 @@
                 <div class="mb-3">
                   <label for="target_bucket" class="form-label">Target Bucket Name</label>
                   <input type="text" class="form-control" id="target_bucket" name="target_bucket" required placeholder="e.g. my-backup-bucket">
-                  <div class="form-text">The bucket on the remote service must already exist.</div>
+                  <div class="form-check mt-2">
+                    <input class="form-check-input" type="checkbox" id="create_remote_bucket" name="create_remote_bucket">
+                    <label class="form-check-label" for="create_remote_bucket">
+                      Create this bucket on the remote server if it doesn't exist
+                    </label>
+                  </div>
                 </div>
                 
                 <button type="submit" class="btn btn-primary">Enable Replication</button>