SG220 ping unstable

[UBC]

I've got two SG220-26 switches (firmware version 1.1.3.1) and both have the same problem.
They randomly stop answering ping for approximately 20 -30 minutes.
We are using a monitoring system (Zabbix) that pings the switches every 60 seconds. But sometimes, let's say 10 times during a week, the switches go offline, not both at the same time, for approximately 20 - 30 minutes.
We have other switches models, for instance SG200, that don't have this problem.
When one SG220-26 doesn't answer ping its management web interface is accessible and works normally. But I cannot ping the switch from any host on the network, even from a machine directly connected to a switch port. There are no VLANs configured.

[UBC]

I do not recommend anyone to buy Small Business 220 Series switches.

Beside the monitoring ping issue that I reported in my previous post the firmware available for 220 series switches lacks many features available on 200 series switches.

[roberto-nepeman]

try this

no security-suite dos icmp-frag-pkts-deny
no security-suite dos icmpv4-ping-max-check
no security-suite dos icmpv6-ping-max-check