Exam N10-008 topic 1 question 150 discussion

Increasing MTU will increase more Runts and CRCs. This is a Cabling issue.

The runt count indicates that the frames received by the switch were too small to be processed. This usually happens when a collision occurs, or a device sends a frame that is shorter than the minimum frame size allowed. If the network administrator has already tried multiple ports on both switches, the issue is most likely not caused by a faulty port or cable. Therefore, the network administrator should try to increase the MTU size on both switches. The MTU (Maximum Transmission Unit) size defines the largest data packet that can be transmitted over a network. If the MTU size is too small, the data packets may need to be fragmented, which can result in performance issues and a high runt count. By increasing the MTU size, the switches should be able to handle larger frames without fragmenting them and reduce the runt count. Therefore, the correct answer is A.

Runts são quadros Ethernet que têm menos de 64 bytes, o que é abaixo do tamanho mínimo permitido para uma trama válida.

An Ethernet frame that is less than the minimum length of 64 bytes with bad FCS (whereas undersize frames < 64 bytes with good FCS). In a half-duplex Ethernet environment, runt frames are almost always caused by collisions. If runt frames occur when collisions are not high or in a full-duplex Ethernet environment, then they are probably the result of under runs or bad software on a network interface card.

Enabling Jumbo frames on the switch wouldnt help in this case, either the switch isnt padding the small frames correctly or there is a media issue.

If MTU size for sending frames do not line up from one switch port to the other, this can include runts due to packets becoming fragmented. If this was an error with the way the cables were configured, you would receive CRC errors, or no connection at all.

A runt is a frame that is less than 64 bytes in size and has a bad CRC. A runt could result from a duplex mismatch or a Layer 1 issue

Runts are frames that are smaller than the minimum frame size (64 bytes) and are typically considered errors in a network. When Layer 2 switches report a high runt count, it often indicates a problem with the physical layer, such as a mismatch or issue with the cabling. By trying multiple ports on both switches and still encountering the issue, it's likely that the problem is not limited to a single port or switch. Given this situation, the most appropriate action is to focus on the common element in the communication path, which is the cable connecting the two switches. Recertifying the cable involves testing its quality, verifying that it meets the required specifications, and ensuring that it is properly terminated. This can help identify and address any physical issues with the cable that might be causing runts.

GPT picks (B) Recertify the cable between both switches: " A "runt" is a term used in networking to describe a frame that is smaller than the minimum frame size allowed by the Ethernet standard. Runt frames can result from various issues, such as collision, signal degradation, or cable problems. Since the problem persists after trying multiple ports on both switches, the issue could be related to the cable connecting the switches. Recertifying the cable involves verifying its integrity, ensuring proper termination, and checking for any signal degradation or cable faults. By addressing potential cable issues, the network administrator can reduce or eliminate the occurrence of runt frames and improve the overall communication between the switches. Options (A) Increasing the MTU size, (C) Performing a factory reset, and (D) Enabling debug logging are not directly related to addressing the issue of high runt count between the switches."

Need to recertify the cable, this is a cabling issue

B. Recertify the cable between both switches.

Runts are when ETHERNET frames that are less that 64 bytes in size. Cabling issue

B. Recertify the cable between both switches. A high runt count usually indicates that packets are being discarded because they are smaller than the minimum allowed frame size, which can be caused by a physical issue with the cable or NIC. By recertifying the cable between the switches, the network administrator can identify and replace any damaged or improperly terminated cables that may be causing the issue.

definitely B - not sure why/how increasing MTU size will help when a runt is when a frame is under 64 bytes

B. Recertify the cable between both switches.

This is similar to broadcast storm caused by cables. B is the right answer

From Mike Meyers "In the past, collisions (which were eliminated with full-duplex Ethernet decades ago) were likely causes of runts. Nowadays, bad wiring and electrical interference are leading causes of runts."