Remote Monitoring & Management Help

Ethernet Errors Check

The Ethernet Errors Check monitors the NIC interfaces on a device for the following issues: Alignment Errors, FCS Errors, Collisions, MAC Receive Errors, MAC Send Errors, Carrier Sense Errors, and frames that are too long.

The Ethernet Errors Check only works with network infrastructure devices, such as switches, routers, fire walls, wireless access points. It will not work on servers, laptops, or workstations.

Basic Check information

Check Type SNMP
Supported Systems/Application Server - Generic, Workstation - Generic, Other, Printer, Scanner/Camera, Switch/Router, and Server - Window

Troubleshooting

Issue Corrective Action
Failed Please check that the correct SNMP community string is configured in Network Discovery for the device
201 Exception OID_TYPE_NOSUCHOBJECT Missing OID object on the device for specific metric

EtherLike-MIB

Object Descriptors Numerical OID
dot3StatsIndex 1.3.6.1.2.1.10.7.2.1.1
dot3StatsAlignmentErrors 1.3.6.1.2.1.10.7.2.1.2
dot3StatsFCSErrors 1.3.6.1.2.1.10.7.2.1.3
dot3Stats1CollisionFrames 1.3.6.1.2.1.10.7.2.1.4
dot3StatsMultipleCollisionFrames 1.3.6.1.2.1.10.7.2.1.5
dot3StatsInternalMacReceiveErrors 1.3.6.1.2.1.10.7.2.1.16
dot3StatsInternalMacTransmitErrors 1.3.6.1.2.1.10.7.2.1.10
dot3StatsCarrierSenseErrors 1.3.6.1.2.1.10.7.2.1.11
dot3StatsFrameTooLongs 1.3.6.1.2.1.10.7.2.1.13

OID/Calculation

Metric Name OID/Calculation Description
Alignment Errors ^ dot3StatsAlignmentErrors An Alignment Error can indicate the following about a received packet:
  • The number of bits in the received packet has an uneven byte count. That is, not an integral multiple of 8.
  • The received packet has a Frame Check Sequence (FCS) error.
  • Alignment Errors often result from MAC layer packet formation problems and cabling problems. These problems cause corruption of data, loss in data and the transmission of packets through more than two cascaded multi-port transceivers.
FCS Errors ^ dot3StatsFCSErrors FCS Errors, a type of cyclic redundancy checking, indicate that frames received by an interface are an integral number of octets long, but do not pass the FCS check.

Both Alignment Errors and FCS Errors can be caused by equipment powering up or down or by noise interference on unshielded twisted-pair (10BASE-T) segments. In a network that complies with the Ethernet standard, FCS Errors or Alignment Errors indicate bit errors during a transmission or reception. A very low rate is acceptable. Although Ethernet allows a 1 in 108 bit error rate, typical Ethernet performance is 1 in 1012 or better.
Collisions ^ dot3Stats1CollisionFrames + ^ dot3StatsMultipleCollisionFrames Collisions indicate that two or more devices detect that the network is idle and try to send packets at exactly the same time within one round-trip delay. Because only one device can transmit at a time, both devices must stop sending and attempt to retransmit. Collisions are detected by the transmitting stations.

The retransmission algorithm helps to ensure that the packets do not retransmit at the same time. However, if the devices retry at nearly the same time, packets can collide again; the process repeats until either the packets finally pass onto the network without collisions, or 16 consecutive collisions occur and the packets are discarded.
MAC Receive Errors ^ dot3StatsInternalMacReceiveErrors MAC receive errors can indicate the malfunction of an Ethernet card on the subnet. You can identify the subnet and possibly the unit in question from the MAC address and the IP number.
MAC Send Errors ^ dot3StatsInternalMacTransmitErrors This type of error indicates that the transmission failed because of an internal MAC sublayer error that is not caused by a collision or a carrier sense error.
Carrier Sense Errors ^ dot3StatsCarrierSenseErrors Indicates that the transmission failed because the carrier was not present during any or all of the transmission attempts.
Frame Too Long ^ dot3StatsFrameTooLongs A packet that is longer than 1518 octets (including FCS octets) can cause a Frames Too Long Error. This type of error is often caused by a malfunction in the jabber protection mechanism on a transceiver, or the presence of excessive noise on the transmission cable.

The threshold value units are measured in packets.