ELS Messages for Address Resolution Protocol (ARP)


ARP.001

Level:
U-INFO
Short Syntax:
ARP.001 Q ovf nt network
Long Syntax:
ARP.001 Queue overflow net network
Description:
An ARP packet was discarded, rather than being queued, because the queue of unprocessed ARP packets was too long. This means that ARP packets are arriving faster than they can be processed. Note that this event does not get counted in ELS, it is instead counted in the ARP console. The counters (kept per input network) can be read using the ARP>STATISTICS command, in the ``input packet overflows'' section.
Cause:
This is often a symptom of a so-called ``ARP storm''. Some packets (usually an IP broadcast) arrive at hosts (usually a popular workstation) which do not recognize the destination address; they then attempt (in contravention of the Host specification) to forward the packet, but to do so they need the ARP mapping. Since they all receive the broadcast at the same time, they all attempt to forward the packet at the same time, and all do an ARP request at the same time.
Action:
Prevail on the appropriate host manufacturer to bring their software into compliance with the specification. In the short term, it may be possible to disable the source of the packets, or cause it to use an address that the misbehaving hosts do recognize as a broadcast.

ARP.002

Level:
P-TRACE
Short Syntax:
ARP.002 Pkt in operation_type hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.002 Packet received operation_type hardware_address_space protocol_type net network ID
Description:
An ARP packet of the type indicated has just arrived for processing.

ARP.003

Level:
U-INFO
Short Syntax:
ARP.003 Unkwn hdw hardware_address_space nt network ID
Long Syntax:
ARP.003 Unknown hardware space hardware_address_space net network ID
Description:
An incoming ARP packet was received on a network which is not using ARP for address translation in any protocol.
Cause:
The gateway is misconfigured.
Action:
Correct the configuration.
Cause:
A protocol is in use on that network which requires the use of ARP, but the router does not support that protocol.
Action:
None.

ARP.004

Level:
UE-ERROR
Short Syntax:
ARP.004 Bd hdw hardware_address_space hardware_address_length nt network ID
Long Syntax:
ARP.004 Bad hardware address space hardware_address_space hardware_address_length nt network ID
Description:
An incoming ARP packet was received with a hardware address space code or hardware address length which does not match the one which should be used on that network.
Cause:
This is probably caused by an error (possible a byte swap problem) in some other equipment on the network.
Action:
Use a network management tool to detect the source host and contact the manufacturer of the equipment and report the problem.

ARP.005

Level:
P-TRACE
Short Syntax:
ARP.005 Unkwn prt protocol_type nt network ID
Long Syntax:
ARP.005 Unknown protocol type protocol_type net network ID
Description:
An incoming ARP packet was received for a protocol for which the router is not using ARP for address translation.
Cause:
The gateway is misconfigured.
Action:
Correct the configuration.
Cause:
A protocol is in use on that network which requires the use of ARP, but the router does not support that protocol.
Action:
None.

ARP.006

Level:
UE-ERROR
Short Syntax:
ARP.006 Bd prt protocol_type protocol_address_length nt network ID
Long Syntax:
ARP.006 Bad protocol address length protocol_type protocol_address_length net network ID
Description:
An incoming ARP packet was received with a protocol address length which does not match the one which should be used on that network.
Cause:
This is probably caused by an error (possible a byte swap problem) in some other equipment on the network.
Action:
Use a network management tool to detect the source host and contact the manufacturer of the equipment and report the problem.

ARP.007

Level:
U-TRACE
Short Syntax:
ARP.007 Mk ent hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.007 Make translation entry hardware_address_space protocol_type net network ID
Description:
An incoming ARP packet addressed to this host contained a mapping which was not in the translation cache. A new cache entry was filled in with the information in the packet.

ARP.008

Level:
UE-ERROR
Short Syntax:
ARP.008 Bd opc operation_type hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.008 Bad operation code operation_type hardware_address_space protocol_type net network ID
Description:
An incoming ARP packet was received with an illegal operation code.
Cause:
This is probably caused by an error (possibly a byte swap problem) in some other equipment on the network.
Action:
Use a network management tool to detect the source host and contact the manufacturer of the equipment and report the problem.

ARP.009

Level:
U-TRACE
Short Syntax:
ARP.009 Rply hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.009 Reply sent hardware_address_space protocol_type net network ID
Description:
An ARP reply is being sent as the result of a request for a translation from another host.

ARP.010

Level:
UI-ERROR
Short Syntax:
ARP.010 Err on rply nt network ID
Long Syntax:
ARP.010 Transmission error on sending reply net network ID
Description:
An outgoing ARP or inverse ARP reply packet was dropped as the result of some problem in the router.
Cause:
There are many potential causes of this problem; an overloaded output queue, a down network, etc.
Action:
Consult logging output from the relevant network subsystem for more information.

ARP.011

Level:
U-TRACE
Short Syntax:
ARP.011 Del ent hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.011 Deleting translation entry hardware_address_space protocol_type net network ID
Description:
A translation cache entry timed out (which was not used or refreshed recently) has been deleted. Consult the ARP manual for more details on controlling this process.

ARP.012

Level:
UI-ERROR
Short Syntax:
ARP.012 No iorb fr rqst nt network ID
Long Syntax:
ARP.012 No buffer for outgoing request packet net network ID
Description:
An outgoing reply packet was dropped as the result of a lack of buffers in the router.
Cause:
There are many potential causes of this problem; temporary overloads, etc.
Action:
Consult logging output from the rest of the router for more information. If the problem persists, contact Customer Service.

ARP.013

Level:
UI-ERROR
Short Syntax:
ARP.013 No mem fr addr nt network ID
Long Syntax:
ARP.013 No memory for address net network ID
Description:
An outgoing reply packet was dropped as the result of a lack of memory in the router.
Cause:
There are many potential causes of this problem.
Action:
Consult logging output from the rest of the router for more information. If the problem persists, contact Customer Service.

ARP.014

Level:
U-TRACE
Short Syntax:
ARP.014 Rqst hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.014 Translation request sent hardware_address_space protocol_type net network ID
Description:
An ARP translation request is being sent as the result of the transmission of a packet from the router for which the translation of another host's address is needed.

ARP.015

Level:
UI-ERROR
Short Syntax:
ARP.015 Err in rqst nt network ID
Long Syntax:
ARP.015 Transmission error in request net network ID
Description:
An outgoing request packet was dropped as the result of some problem in the router.
Cause:
There are many potential causes of this problem; an overloaded output queue, a down network, etc.
Action:
Consult logging output from the relevant network subsystem for more information.

ARP.016

Level:
P-TRACE
Short Syntax:
ARP.016 unkn dst prot ad nt network ID
Long Syntax:
ARP.016 Unknown destination protocol address net network ID
Description:
This message is generated when an ARP request specifies an unknown protocol address (i.e. request not for this router).
Cause:
ARP request for a host on this network that is not this router.
Action:
None needed. This is normal for the ARP protocol, all requests are sent as broadcasts.

ARP.017

Level:
UI-ERROR
Short Syntax:
ARP.017 Rqst send failed rsn reason_code nt network ID
Long Syntax:
ARP.017 Transmission of request failed for reason reason_code net network ID
Description:
An outgoing ARP request packet was dropped as the result of some problem in the router. The reason_code gives the cause.
Cause:
Miscellaneous handler error. (Reason code 1.)
Action:
Check for error messages from handler for network_name.
Cause:
Output queue overflow, or other flow control. (Reason code 2.)
Action:
Alleviate congestion.
Cause:
Network down. (Reason code 3.)
Action:
See why handler thinks network is down.
Cause:
Dropped by handler to avoid looping, or bad broadcast. (Reason code 4.)
Action:
Check configuration.
Cause:
Host down. (Reason code 5.)
Action:
See why handler thinks host is down.

ARP.018

Level:
UI-ERROR
Short Syntax:
ARP.018 rcv: No mem for cache ent, prot protocol_type nt network ID
Long Syntax:
ARP.018 receive: No memory for cache entry, protocol protocol_type net network ID
Description:
During the input processing of an ARP packet, the router did not have memory available to make an ARP cache entry for the given protocol.
Cause:
The router is extremely low on heap memory.
Action:
Find some way to reduce memory usage.

ARP.019

Level:
UI-ERROR
Short Syntax:
ARP.019 xmt: No mem for cache ent, prot protocol_type nt network ID
Long Syntax:
ARP.019 transmit: No memory for cache entry, protocol protocol_type net network ID
Description:
During the output processing of an ARP packet, the router did not have memory available to make an ARP cache entry for the given protocol.
Cause:
The router is extremely low on heap memory.
Action:
Find someway to reduce memory usage.

ARP.020

Level:
U-TRACE
Short Syntax:
ARP.020 Inverse Rply sent hardware_address_space protocol_type nt network ID
Long Syntax:
ARP.020 Inverse Reply sent hardware_address_space protocol_type net network ID
Description:
An inverse ARP reply is being sent as the result of a request for a translation from another host.

ARP.021

Level:
P-TRACE
Short Syntax:
ARP.021 inv arp req drp, no prot addr for prot protocol_type nt network ID
Long Syntax:
ARP.021 inverse ARP request dropped, no protocol address protocol_type nt network ID
Description:
This message is generated when an inverse ARP request arrives but cannot be answered and is discarded because the router does not have a protocol address for the requested protocol on the interface.
Cause:
The router either does not have the protocol configured on the interface, or protocol initialization on the interface is not complete, or inverse ARP is not configured for this protocol. Inverse ARP is not supported for this protocol.
Action:
None needed. This is normal.
Cause:
If the protocol requested is AppleTalk, The router may still be in the process of going through its probe logic before the AppleTalk protocol address is valid.
Action:
None needed. This is normal.

ARP.022

Level:
U-TRACE
Short Syntax:
ARP.022 Inv Rqst sent hardware_address_space protocol_type to hardware_address nt network ID
Long Syntax:
ARP.022 Inverse Request sent hardware_address_space protocol_type to hardware_address net network ID
Description:
An inverse ARP request is being sent in an attempt to inform the other side of our protocol address.

ARP.023

Level:
UI-ERROR
Short Syntax:
ARP.023 dup proto addr on net: proto = protocol_type addr = addr_string
Long Syntax:
ARP.023 Duplicate protocol address on network: protocol = protocol_type address = addr_string
Description:
An ARP request was received with a source address that matches one of routers addresses