I have an MX100.
I have been seeing this issue since I increased our bandwidth to 500 Mb/s the speed drops out about every 25 seconds when transferring large files. I usually notice this during cloud backups, but have seen it with other large file transfers also. I am looking for suggestions to try and resolve the issue since it drastically increases the time needed for the transfer and can cause the transfer to fail going to FTP sites.
Hi ,
You would probably need to take a packet capture and see how TCP is handling / reacting.
Look for TCP zero and/or TCP window full.
Do you see any packetloss on that link ?
Have you configured traffic shapping with the configured WAN speed ?
I do not see any TCP Zero or Window full messages. I do see a lot of "Ignored Unknown Record" messages in Wireshark.
I am seeing some packet loss but not on the same frequency as the transfer drop.
I do have traffic shaping configured but in this case the source has been whitelisted so it can use the full bandwidth.
Hi @Mizinia - what does the CPU look like on the MX? How many clients do you have connected?
CPU doesn't look like it ever gets to 100% but it does get high (looks like >85%) during large transfers. the system shows about 450 clients.
In that case , that might be related to CPU usage. CPU must be spiking above 85% in that 1 minute window. The stats are tracked every minute if I'm not mistaken.
I had narrowed it down to needing a newer/larger appliance that was rated for higher throughput. I don't like the throw more money at it approach so I thought I would throw the question out to see if I was missing some configuration that would clear up the issue.
100% with you there !
Do you have a way to test the transfer when the appliance is less utilized ? Let's say during the week-end or the night ?
i have tried with almost no users on. i see the same issue.
99% likely you are seeing normal TCP windowing.
I wouldn't do anything about this ... you could try enabling TCP timestamps to see if it flattens it out a little bit.
netsh int tcp set global timestamps=enable
Ideally you would do this on the machines on both ends.
I added the timestamps. we will see if that helps.