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I have a synology 1511+ nas. My network transfer speeds are very slow, < 1meg a sec in some cases. It's next to unbearable.

Anyway was reading about this thing that said to ping it using the -f settings and here's the result.

C:\Users\Jason Fonseca>ping -f -l 2000

Pinging with 2000 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

The website said to adjust the MTU settings in order to get rid of this message but I don't know what to change.

Can anyone recommend what needs to be done here?


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Is WLAN or another wireless technology involved somehow? – Turbo J Jun 1 '11 at 14:46
>ping -f -l 2000

This command tries to send 2000 Bytes at once, while an ethernet frame can transmit only a bit less than 1500 Bytes by default.

Changing the MTU of your Ethernet card is not recommended unless you know exactly what you do.

One reason is that every switch/bridge between your PC and the NAS must support the bigger MTU too. And your ethernet card may not even have the capability to send/receive ethernet frames bigger than 1500 Bytes.

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