Cisco MDS-9124 Troubleshooting Guide - Page 427

Chapter 20 Troubleshooting IP Storage Services iSCSI TCP Performance Issues Send documentation comments to [email protected] iSCSI Node name is iqn.1987-05.com.cisco:02.75af2f95624c.shark-nas iSCSI alias name: SHARK-NAS Node WWN is 20:00:00:0c:30:57:5e:c2 (dynamic) Member of vsans: 777, 778 Number of Virtual n_ports: 1 Virtual Port WWN is 20:00:00:0c:30:57:5e:c2 (configured) Interface iSCSI 2/1, Portal group tag is 0x1001 VSAN ID 0, FCID 0x 0 No. of FC sessions: 1 No. of iSCSI sessions: 1 iSCSI session details Target node: Statistics: PDU: Command: 0, Response: 0 Bytes: TX: 0, RX: 0 Number of connection: 1 TCP parameters Local 10.48.69.250:3260, Remote 10.48.69.233:1026 Path MTU: 1500 bytes Retransmission timeout: 300 ms Round trip time: Smoothed 150 ms, Variance: 31 Advertized window: Current: 998 KB, Maximum: 1000 KB, Scale: 4 Peer receive window: Current: 1000 KB, Maximum: 1000 KB, Scale: 4 Congestion window: Current: 12 KB VSAN ID 777, FCID 0x610001 No. of FC sessions: 1 No. of iSCSI sessions: 1 iSCSI session details Target node: shark_nas Statistics: PDU: Command: 392051, Response: 392042 Bytes: TX: 25692593152, RX: 0 Number of connection: 1 TCP parameters Local 10.48.69.250:3260, Remote 10.48.69.233:1057 Path MTU: 1500 bytes Retransmission timeout: 300 ms Round trip time: Smoothed 2 ms, Variance: 1 (Watch out for these numbers. The output is for a TCP session that goes only through one Gigabit Ethernet switch. When there are multiple router hops, as well as WAN links in the middle, the RTT will grow, and the variance will fluctuate with higher values. You may need to adjust the retransmission timeout.) Advertized window: Current: 1000 KB, Maximum: 1000 KB, Scale: 4 (This is the window size set on the Windows client. See Figure 20-14.) Peer receive window: Current: 1000 KB, Maximum: 1000 KB, Scale: 4 (This is the window size set on the IPS iSCSI interface. See Figure 20-14.) OL-9285-05 Cisco MDS 9000 Family Troubleshooting Guide, Release 3.x 20-53