Duplicate IP address detection by a DHCP relay agent
First Claim
Patent Images
1. A method, comprising:
- upon determining, by a Dynamic Host Configuration Protocol (DHCP) relay agent positioned in a network between DHCP clients and one or more DHCP servers, that the one or more servers have become unavailable, assigning a first IP address to a first DHCP client of the DHCP clients;
upon determining that the one or more DHCP servers are available, identifying, at the DHCP relay agent, a list of DHCP clients that have valid IP address leases from the one or more DHCP servers;
monitoring, at the DHCP relay agent, network traffic originating from the DHCP clients and passing through the DHCP relay agent; and
determining, at the DHCP relay agent, that the first DHCP client is using the first IP address that creates a potential duplicate IP address conflict, when the identified list of DHCP clients indicates that the first DHCP client does not have a valid lease for the first IP address and when the monitored network traffic indicates that no other device within the network is currently using the first IP address; and
performing a corrective action for the potential duplicate IP address conflict, comprising;
transmitting, at the DHCP relay agent, a request for a lease of the first IP address and that specifies a media access control (MAC) address of the first DHCP client, to one of the one or more DHCP servers, thereby resolving the potential duplicate IP address conflict without involvement of the first DHCP client.
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Accused Products
Abstract
Techniques are described for detecting duplicate IP addresses at a DHCP relay agent. Embodiments identify a list of DHCP clients that have valid IP address leases from one or more DHCP servers. Additionally, network traffic from a first node passing through the DHCP relay agent is monitored. Embodiments then determine whether the first node is using a duplicate IP address, based on the monitored network traffic and the identified list of DHCP clients.
32 Citations
12 Claims
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1. A method, comprising:
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upon determining, by a Dynamic Host Configuration Protocol (DHCP) relay agent positioned in a network between DHCP clients and one or more DHCP servers, that the one or more servers have become unavailable, assigning a first IP address to a first DHCP client of the DHCP clients; upon determining that the one or more DHCP servers are available, identifying, at the DHCP relay agent, a list of DHCP clients that have valid IP address leases from the one or more DHCP servers; monitoring, at the DHCP relay agent, network traffic originating from the DHCP clients and passing through the DHCP relay agent; and determining, at the DHCP relay agent, that the first DHCP client is using the first IP address that creates a potential duplicate IP address conflict, when the identified list of DHCP clients indicates that the first DHCP client does not have a valid lease for the first IP address and when the monitored network traffic indicates that no other device within the network is currently using the first IP address; and performing a corrective action for the potential duplicate IP address conflict, comprising; transmitting, at the DHCP relay agent, a request for a lease of the first IP address and that specifies a media access control (MAC) address of the first DHCP client, to one of the one or more DHCP servers, thereby resolving the potential duplicate IP address conflict without involvement of the first DHCP client. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification