---
name: cis-ts-offline
title: Why is my website offline?
description: 'Here is what you might see: `IBM CIS can''t connect to the origin server (error 521, 522, 523)`.'
last-updated: 2025-02-24
---

> ## Documentation Index
> The table of contents for this documentation set is at https://cloud.ibm.com/docs/cis?format=markdown
> The index for all IBM Cloud docs is at: https://cloud.ibm.com/docs/llms.txt
> Use these files to discover more information as needed.

# Why is my website offline?
{: #troubleshooting-cis-website-offline}
{: troubleshoot}

Here is what you might see: `IBM CIS can't connect to the origin server (error 521, 522, 523)`.

**Website offline - no cached version**
{: tsSymptoms}


1. The server is online, but it is blocking the CIS request.
2. The origin server is offline and CISS does not have a backup website image
{: tsCauses}


* Verify that the CIS IP addresses are allowlisted.
* Make sure that CIS IPs are not being rate-limited.
* Review the list of [IPs to allowlist](https://cloud.ibm.com/docs/cis?topic=cis-cis-allowlisted-ip-addresses&format=markdown).
{: tsResolve}