One of our clients has an SRX240H in their office that occasionally is dropping connections going LAN to WAN. For example: they could be on an IRC server and they will drop out for 2 minutes and then come back or an HTTP download will die half way through. We've ruled out upstream problems with the ISP.
What steps can I take to diagnose this? We only have remote web access to this device, but can probably get SSH if required.
UPDATE
I shall find out what version of JunOS it is back in the office tomorrow.
The scenario is the clients office has a fibre connection to our DC with two VLANs, one presenting internet and one presenting their office infrastructure (AD, file servers, etc). It's a gigabit connection, and they use it as such to access their file server etc all day.
It's possible it's overloading it, but on paper it should be MORE than capable.