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New Member

SG300 Dropping Connections but SG500 not?

We recently moved to a new physical office, and I was in charge of spec'ing out and ordering networking gear. Everything is brand new, from the wires to the switches to the Comcast modem (though that is also Cisco branded as well).


We went with the SG500-52 model for PoE for powering Polycom-based RingCentral VoIP phones. This switch is plugged directly into the modem and does not seem to be having problems. We also plug two Meraki AP's (powered using PoE) into them (MR16 and MR18) and neither of these are having problems.


The SG300-52 is plugged into the second of four ports on the back of the Comcast modem. People plugged into the SG300-52 are getting intermittent internet issues. They are getting signed out of Google Chat, SSH sessions on the server are getting dropped, and internet is going from fast and speedy to slow and unusable.


The "Master" DHCP server is the Comcast-modem (acting as the router) and each switch is plugged directly into the modem. I have individuals using the network now, so I don't want to do any huge maintenance windows too soon here. I unboxed the equipment, installed it in the rack, and wired everything up. I have updated the time on the switch, set a new password, but that is it. I have not done a firmware upgrade yet because I want to try anything else first. I also hear mixed comments on how long a firmware upgrade will take.


What would you recommend I do to try and gain stability on the SG300-52-connected devices? Switching from wired to Wireless (and keeping all else constant) resolves all the issues that the individuals are having (not getting signed out of chat, no dropped SSH sessions, and consistant/reliable internet).


Should I stack the switches, and make only the SG500-52 plugged into the modem? Right now they both are. Any ideas?

Everyone's tags (1)
New Member

Ive updated the firmware and

Ive updated the firmware and filesystem to the newest versions and I am experiencing less problems, but I am still having problems. Any ideas? I also have a case with Cisco.

Cisco Employee

 I have a similar problem


I have a similar problem with the SG300-10P. I disable the green ethernet power saving feature hoping to fix this issues, but still having timeout issues. The port link lights turn off and I don't know why. Some sort of inactivity timeout? The workstations lose the dhcp lease (set for 7 days). Not sure what else to try.

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