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5-11
Cisco MDS 9000 Family Troubleshooting Guide
OL-5183-02, Cisco MDS SAN-OS Release 1.3
Chapter 5 Troubleshooting IP Storage Issues
Troubleshooting FCIP Connections
6 Attempts for active connections, 3 close of connections
TCP Parameters
Path MTU 1500 bytes
Current retransmission timeout is 100 ms <<< Default, adjusted under
Round trip time: Smoothed 10 ms, Variance: 5
(This is the calculated round trip time of the FCIP tunnel. Large round trip times will require increasing
the TCP window size under the FCIP profile.)
Advertized window: Current: 64 KB, Maximum: 64 KB, Scale: 1
(This is the local advertised TCP window size, and the default is 64 KB.)
Peer receive window: Current: 64 KB, Maximum: 64 KB, Scale: 1
(This is the remote end point advertised TCP window size.)
Congestion window: Current: 2 KB
(This is the minimum windows size used during congestion, and is not configurable.)
5 minutes input rate 136 bits/sec, 17 bytes/sec, 0 frames/sec
5 minutes output rate 136 bits/sec, 17 bytes/sec, 0 frames/sec
2288 frames input, 211504 bytes
2288 Class F frames input, 211504 bytes
0 Class 2/3 frames input, 0 bytes
0 Error frames
2288 frames output, 211520 bytes
2288 Class F frames output, 211520 bytes
0 Class 2/3 frames output, 0 bytes
0 Error frames 0 reass frames
MDS1# show interface fcip 28 brief
-------------------------------------------------------------------------------
Interface Vsan Admin Admin Status Oper Profile Port-channel
Mode Trunk Mode
Mode
-------------------------------------------------------------------------------
fcip28 1 auto on trunking TE 28 --
MDS1# show interface fcip 28 counters bri
-------------------------------------------------------------------------------
Interface Input (rate is 5 min avg) Output (rate is 5 min avg)
----------------------------- -----------------------------
Rate Total Rate Total
Mbits/s Frames Mbits/s Frames
-------------------------------------------------------------------------------
fcip28 18 0 18 0
(This is the frames that averaged over 5 minutes and the total count of frames since the last clear
counters command was issued, or since the last tunnel up.)
Verify default 2 tcp connections are established for each fcip tunnel configured, one for control traffic
and one for data traffic
MDS1# show ips stats tcp interface gigabitethernet 2/8
TCP Statistics for port GigabitEthernet2/8
Connection Stats
6 active openings, 8 accepts
6 failed attempts, 0 reset received, 8 established
Segment stats
295930 received, 1131824 sent, 109 retransmitted
(Excessive retransmits indicate possible core drops and/or that the TCP window size should be adjusted.)
0 bad segments received, 0 reset sent