Allied Telesis Rapier i Series manual Displaying log entries, Show log command is also very useful

Page 24

Troubleshooting

Displaying log entries

The show log command is also very useful:

Manager > sh log

Date/Time S Mod Type SType Message

------------------------------------------------------------------------

02	21:42:55 3	DHCP DHCPS ADD		Adding new entry [chaddr
				00-11-22-33-44-15],
				clientIP 2.2.2.2, vlan1, port3, serverIP
				0.0.0.0, Expires N/A (static entry)
02	21:43:20 4	DHCP DHCPS	FAIL	Error adding entry [chaddr
				00-11-22-33-44-16].
				Adding another entry will exceed the
				configured MAXLEASES of 1 for port 3
02	21:43:20 4	CH MSG	ERROR	Static DHCP Snooping entry could not be
				added.
				Check log for details
02	21:43:56 3	DHCP DHCPS ADD		Adding new entry [chaddr
				00-11-22-33-44-16],

clientIP 2.2.2.2, vlan1, port7, serverIP 0.0.0.0, Expires N/A (static entry)

Page 24 AlliedWare™ OS How To Note: DHCP Snooping on Rapier-style switches

Image 24

Contents AlliedWareTM OS IntroductionThis document contains the following contents Related How To Notes Minimum configurationDhcp snooping Database survival across reboots DatabaseDhcp snooping database time-out Verifying the status of snooped usersList of terms ARP SecurityTrusted and non-trusted ports Enabling Dhcp snoopingStatic binding Completely removing the Dhcp snooping database So the database is emptyDhcp Option Protocol details Example PacketDhcp Message Type = Dhcp Request Configuring Option AnalysisConfiguring filtering Dhcp filteringTo enable Dhcp snooping ARP security Dhcp snooping filter show commandARP security Resource considerationsIf ARP security is enabled, add Or if ARP security is enabled, isExample on a Rapier Configuration examples Configure a private Vlan for customersEnable Dhcp snooping and Option 82 support Add the tagged uplink ports to the VlanAdd the untagged ports for the customers Define the Dhcp snooping trusted portsCreate a set of QoS classifiers Define the upstream QoS flow groupsCreate a traffic class for all upstream flow groups Configure two VLANs for layer 3 access to the Dhcp server Add ports to the VLANsFor layer 3 support, enable the Bootp Relay Define the Dhcp snooping trusted portCreate a set of QoS classifiers Troubleshooting No trusted ports configuredDHCPSNProcess 0b4333cc Dhcp Snooping pkt for Vlan From port DHCPSNProcess 0b4333cc TaggedNone UntaggedNoneDhcp client continually sends requests instead of a discover Maximum number of leases is exceededSwitch is dropping ARPs Manager set dhcpsnooping port=3 maxleases=2Dhcpsnarp 01a6f5ec ARP to be forwarded, sender validated Dhcpsnarp 02680e6c ARP to be forwarded, sender validated Trusted portsShow log command is also very useful Displaying log entriesAppendix 1 ISC Dhcp server C613-16086-00 REV B