Layer 7: Application Layer
Overview: Layer includes issues related to protocols such as resource sharing or remote file access
Technologies in Scope: http(s), DNS, DHCP, RTSP
Tools for Troubleshooting: SSH
- Does the DHCP server show a reservation for the mac address of the device?
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- PowerShell Example:
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- UI Example:
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- Is DNS working on the customer network where device resides?
- Does client network allow DNS (TCP port 53) to a layer 3 IP address (sometimes public, sometimes private)?
- Does the DNS server that DHCP is distributing to the device respond to DNS queries?
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- Note: address will not match screenshot
- These are behind load balancers/DHCP
- Simply ensure the DNS server is resolving the FQDN to an IP address
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- Alternatively, issue a simple ping to google. This will verify if the DNS server provided on the VLAN via DHCP is properly resolving host names.
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