Website Down Checker

See whether a site was up at our last check and when it last went down.

Current Status

Status
Active
Server Type
nginx
Page Title
TopTu - 专业网络拓扑图设计工具 | 在线画拓扑图 | 机房设备管理
Meta Description
TopTu 是一款专业的在线网络拓扑图设计工具,支持拖拽式作图、50+ 网络设备图标、云端同步、团队协作、扫码分享,可导出 PDF / PNG。适合网络工程师、运维、集成商绘制机房拓扑、办公网结构图、园区网方案。
Meta Keywords
网络拓扑图,拓扑图工具,在线画拓扑图,网络拓扑图软件,机房拓扑图,交换机拓扑图,拓扑图在线编辑,network topology,TopTu,网络图,网络架构图,网工工具
Last Checked
just now
Last Status Change
No change observed
Last Downtime
Never observed down

Observed Changes

DateStatusServer
8/9/2026, 10:29:06 PMActivenginx

Don't just check uptime once — watch it 24/7

This is a one-time check. Turn on monitoring and we'll watch the domains that matter to you continuously, notifying you the moment anything moves across all three signals:

Uptime monitor with 7-day uptime percentage, failed checks, average latency by region, and daily outages

Uptime

We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.

DNS changes

We watch NS, MX, CAA, CNAME, TXT and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.

TLS certificate

We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.

Monitor uptime free

Free for your first domain: uptime, DNS, and certificate together. No credit card.

About Website Uptime Monitoring

This page shows whether we could reach a website the last time we checked it. We also keep a record of when it went down and came back, so you can see whether an outage is new or has happened before. For each site we show:

  • Website availability and response status
  • Server software and configuration
  • Meta information including titles and descriptions
  • Historical uptime patterns

What this page reports

  • Last status change: When we last saw a site switch between reachable and unreachable
  • Last downtime: When a site was most recently seen down, and whether it has come back
  • Server and meta information: The server software, page title and meta tags we last observed

We check a domain at most once a day and record an observation only when something changes, so these are the times a change was seen rather than the exact moment it happened. For continuous, minute-by-minute checks with alerting, use website monitoring.


Disclaimer: Who.is is not affiliated with, endorsed by, or connected to any of the domains displayed on this page. We provide this information as a public service for informational purposes only.