Why doesn’t the website open via DNS, although it’s accessible via IP address? Hello. I have a problem: a website hosted at IP address 192.168.0.60 is accessible when accessed directly via IP, but doesn’t open when accessed via domain name. When trying to access via DNS, I get a timeout error ‘timeout waiting for response from the site’. What could be the causes of this problem and how can it be fixed?
When a website is accessible via IP address but not via domain name, this indicates a DNS resolution issue. This condition typically means that your device can connect to the server directly via IP, but the DNS system cannot resolve the domain name to the corresponding IP address. The main causes can include DNS server failures, network connectivity issues to DNS servers, incorrect DNS client configuration, or blocking of DNS requests on network equipment.
Table of Contents
- Basic Causes of the Problem
- Step-by-Step Diagnostics
- DNS Server Solutions
- Client Configuration
- Preventive Measures
- Conclusion
Basic Causes of the Problem
DNS resolution problems, where access via IP works but via domain doesn’t, can occur due to several main reasons:
1. DNS Server Configuration Errors
- Incorrect DNS forwarder settings
- Errors in DNS zones
- Domain delegation issues
- Overloaded DNS server
2. Network Issues
- No connection to DNS servers
- DNS query blocking by firewall
- Routing issues to DNS servers
3. Client Issues
- Incorrect DNS client settings
- Use of non-functional DNS servers
- DNS cache problems
Important: If access via IP works, this confirms that the network connection and the server itself are functioning properly. The problem is definitely in the name resolution system.
Step-by-Step Diagnostics
To determine the exact cause of the problem, perform the following steps:
1. Check DNS resolution from the DNS server itself
nslookup your_domain
If the query is successful, the problem may be on the client or in the network between the client and DNS server. If the query fails, the problem is with the DNS server itself.
2. Check network connectivity to DNS servers
ping 192.168.0.60 # or your DNS server IP
If ping doesn’t work, check your network configuration and firewalls.
3. Use DNS diagnostic tools
dig your_domain # for Linux/macOS
nslookup your_domain # for Windows
These commands will show detailed information about the name resolution process.
4. Check DNS cache
ipconfig /flushdns # for Windows
sudo systemd-resolve --flush-caches # for Linux
DNS Server Solutions
If the problem is found on the DNS server, perform the following actions:
1. Check DNS forwarder settings
- Ensure correct IP addresses are specified for forwarders
- Verify that forwarders are accessible from the network
- If necessary, change or update the settings source
2. Check DNS zone status
- Ensure zones are not suspended
- Verify correctness of A, AAAA, CNAME records
- Make sure records don’t contain errors source
3. Check root hints
- Ensure root DNS servers are accessible
- Verify that the server can ping root servers by IP
- If necessary, update root hints source
4. For pfSense users
- Disable DHCP-lease registration in unbound
- Check DNS Resolver settings
- Restart the DNS service source
Client Configuration
The problem may also be in the client settings:
1. Change DNS servers
- Use public DNS servers (8.8.8.8, 1.1.1.1)
- Verify that current DNS servers are accessible
- Temporarily switch to another DNS for diagnostics source
2. Check network interface settings
- Ensure correct DNS servers are specified
- Check DHCP settings
- If necessary, specify DNS servers manually
3. Check hosts file
- Open the hosts file (C:\Windows\System32\drivers\etc\hosts in Windows)
- Make sure there are no incorrect entries
- Add a temporary entry for your domain if needed
4. Check firewalls and antivirus
- Temporarily disable firewall for testing
- Check antivirus settings for DNS blocking
- Ensure traffic on port 53 (TCP/UDP) is allowed source
Preventive Measures
To avoid similar problems in the future:
1. Monitor DNS servers
- Set up DNS server availability monitoring
- Monitor server load
- Use multiple DNS servers for redundancy
2. Regular maintenance
- Periodically clear DNS cache
- Update DNS server software
- Check DNS record validity
3. Redundancy
- Configure backup DNS servers
- Use DNS caching services
- Create DNS zone backups
4. Documentation
- Maintain DNS configuration documentation
- Save change history
- Create action plans for failures
Conclusion
The problem of accessing a website via domain name when IP address access works is a common situation that indicates a failure in the DNS resolution system. The main causes can be on the client side (incorrect DNS settings, cache issues) or on the server side (configuration errors, overload, network problems).
For diagnostics, it’s important to sequentially check:
- Network connectivity to DNS servers
- DNS server functionality
- DNS client configuration
- Presence of blocks on network equipment
In most cases, the problem can be solved by clearing the DNS cache, changing DNS servers, or fixing the DNS server configuration. Regular maintenance and monitoring will help avoid such problems in the future.