Hello All,
We are receiving complaints from remote users stating that they are experiencing slowness while accessing a particular File server at one of our service center (Costa Rica). Basically, their upload and download speed is constantly at 355 kbps.
But they are not facing any slowness when they access network drives in a different data center. From this we assumed that issue is at our service center and continued to troubleshoot.
Here is our findings.
* From remote users machine, we issued continuous ping to the file server, we observed intermittent packet drops but there was no latency.
*We initiated file copy from file server at service center to remote user machine. With help of Wireshark packet capture, we observed that there were a lot a TCP re-transmissions it means that the tcp packet is getting lost somewhere in the transit.
*We checked the performance with the users at the service center, they reported no issues. Only remote users are experiencing slowness.
*We opened a ticket with service center ISP for intermittent packet drops and ISP performed some tests confirmed that there is no issue at their end.
*Packet drops is between 1%-2%.
*We are seeing input errors on the WAN interface (Connection between WAN router and ISP) and LAN interface (Connection between WAN router and access switch)
WMT-CR-SJ-RTR#sh int GigabitEthernet0/0 | i drops|error [WAN interface]
Input queue: 0/75/0/54 (size/max/drops/flushes); Total output drops: 239
992 input errors, 0 CRC, 0 frame, 713158 overrun, 0 ignored
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
WMT-CR-SJ-RTR#sh int GigabitEthernet0/1 | i drops|error [LAN interface]
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
552 input errors, 0 CRC, 0 frame, 276 overrun, 0 ignored
0 output errors, 0 collisions, 0 interface resets
11067 unknown protocol drops
*Also, we are seeing high rate output drops on the interface where file server is connected to access switch.
WMT-CR-SJ-SW1#sh int gi 2/0/22 | i drop|error|broadcasts
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 9458
Received 108407 broadcasts (3956 multicasts)
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
* I have attached qos information, please help us to isolate the issue.
Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 54 WS-C3750X-48P 15.0(2)SE C3750E-UNIVERSALK9-M
2 54 WS-C3750X-48 15.0(2)SE C3750E-UNIVERSALK9-M
