SG300-20 performance issues / slow throughput & packets with errors

[MikeB____]

Issues:

• Slow throughput, between 150Mbps to 500Mbps (max) with only two computers connected
• About 0.3% packets are “Packets with Error”, of which almost all identified as “Internal MAC Receive Errors”
• Speed about 100Mbps when more computers are added

Configuration: upgrade to 1.4.0.88, reboot with “Restore to Factory Defaults”, no other changes

Switch: SG300-20

PID VID: SRW2016-K9 V02

Firmware Version (Active Image): 1.4.0.88

Firmware MD5 Checksum (Active Image): 66ab3618cb29023da5ce7c2177e6c3d4

Boot Version: 1.3.5.06

Boot MD5 Checksum: da44c9c583e5a8a274f911c4d16f501e

The two computers are Windows 7 machines or Synology rack stations, all with SDDs and 1Gpbs network cards. When using an unmanaged switch I constantly saturate the network at about 800Mbps with any combinations of machines and cables. Speed was measured with LAN_SpeedTest.exe and jperf-2.0.2

Things I tried:

• Different ports on SG30-20: not a significant difference, in certain cases the “Packets with Error” percentage is lower
• Different network cables: all cables tested OK, both with the Cooper Test and in the unmanaged switch test (see above)
• Every single firmware since 1.3.0.62, with “Restore to Factory Defaults”
• Reload the new bootloader firmware
• Unplug the power cable (after switch started) and let it rest for a while
• Pressing the reset button to “Restore to Factory Defaults”

Any thoughts?

[Aleksandra Dargiel · Accepted solution]

Hi Mike,

What is the temperature it is operating in? Can you test in cooler place?

Otherwise you might want to call Cisco Small Business Support team and open the ticket to verify if this is not a hardware issue:

http://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

Regards,

Aleksandra

[MikeB____]

Aleksandra,

Thank you for your suggestions.

The switch is in inside a well-ventilated rack in my office (ambient temperature is about 78F). The switch is warm to touch, but not hot. To be thorough, I let the switch cool for 1 hour (unplugged the power cord) and set up a fan to blow air on the switch. It did not make a difference from the previous results.

However, I noticed a pattern:

- Ports 1-16 report errors (mostly “Internal MAC Receive Errors”) and have low throughput speeds (about 100-150 Mbps)

- Ports 17-20 report zero errors and have relatively high throughput speeds (about 300-500 Mbps, however I am not able to saturate the 1Gbps connection)

- Mixing Ports 1-16 and 17-20 shows speeds about 200Mbps

I will contact Cisco Small Business Support.

[Aleksandra Dargiel]

Hi Mike,

Please message me privately your case number.

Regards,

Aleksandra

[MikeB____ · Accepted solution]

Cisco Small Business Support addressed the issue - most likely hardware related.

Suggestion for others contacting support: for basic diagnostics, it helps if the switch is not in production; it should be connected only to few testing machines.

Thank you!

[Neptune Computers]

how to resoved that issue hanging & noise issue that switch

[Martin Aleksandrov]

Hi,

Since it seems to be a hardware problem you will need to contact Cisco TAC by calling one of the following numbers: 

https://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

Thanks