Table Of Contents
T Commands
tail
tcp-connection
tcp cwm
tcp keepalive-timeout
tcp maximum-bandwidth
tcp max-retransmissions
tcp minimum-retransmit time
tcp pmtu-enable
tcp qos control
tcp sack-enable
tcp send-buffer-size
telnet
telnet server enable
terminal
time-stamp
traceroute
trunk protocol enable
T Commands
The commands in this chapter apply to the Cisco MDS 9000 Family of multilayer directors and fabric switches. All commands are shown here in alphabetical order regardless of command mode. See the "Command Modes" section to determine the appropriate mode for each command. For more information, refer to the Cisco MDS 9000 Family Configuration Guide.
•tail
•tcp-connection
•tcp cwm
•tcp keepalive-timeout
•tcp maximum-bandwidth
•tcp max-retransmissions
•tcp minimum-retransmit time
•tcp pmtu-enable
•tcp qos control
•tcp sack-enable
•tcp send-buffer-size
•telnet
•telnet server enable
•terminal
•time-stamp
•traceroute
•trunk protocol enable
tail
To display the last lines (tail end) of a specified file, use the tail command in EXEC mode.
tail filename [number-of-lines]
Syntax Description
filename
|
The name of the file for which you want to view the last lines.
|
number-of-lines
|
(Optional) The number of lines you want to view. If you do not specify the number of lines, the last 10 lines are displayed.
|
Defaults
None.
Command Modes
EXEC mode.
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
You need two separate CLI terminals to use this command. In one terminal, execute the run-script or any other desired command. In the other, issue the tail command for the mylog file. In the second terminal, you will see the last lines of the mylog file (as it grows) that is being saved in response to the command issued in the first terminal.
If you specify a long file and would like to exit in the middle, enter Ctrl-c to exit this command.
Examples
The following example displays the last lines (tail end) of a specified file.
switch# run-script slot0:test mylog
In another terminal, issue the tail command for the mylog file.
In the second CLI terminal, you see the last lines of the mylog file (as it grows) that is being saved in response to the command issued in the first terminal.
tcp-connection
To configure the number of TCP connections for the FCIP interface, use the tcp-connection option. To revert to the default of two attempts, use the no form of the option.
tcp-connection number
no tcp-connection number
Syntax Description
tcp-connection
|
Configures the number of TCP connection attempts.
|
number
|
Enters the number of attempts (1 or 2).
|
Defaults
None.
Command Modes
Configuration mode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
Access this command from the switch(config-if)# submode.
Use the tcp-connection option to specify the number of TCP connections from a FCIP link. By default, the switch tries two (2) TCP connections for each FCIP link.
Examples
switch(config)# interface fcip 50
switch(config-if)# tcp-connection 1
switch(config-if)# no tcp-connection 1
Related Commands
Command
|
Description
|
show interface fcip
|
Displays an interface configuration for a specified FCIP interface.
|
tcp cwm
To configure congestion window monitoring (cwm) TCP parameters in a Cisco MDS 9000 Family switch, use the tcp cwm command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp cwm (burstsize burstsize)
no tcp cwm (burstsize burstsize)
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
cwm
|
Enables congestion monitoring.
|
burstsize
|
Configures TCP burstsize.
|
burstsize
|
Specifies the burstsize ranging from 10 to 100 KB.
|
Defaults
None.
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
Use these TCP parameters to control TCP retransmission behavior in a switch.
Examples
The following example configures a FCIP profile and enables congestion monitoring.
switch(config)# fcip profile 5
switch(config-profile)# tcp cwm
The following example assigns the burstsize value at 20 KB:
switch(config-profile)# tcp cwm burstsize 20
The following example disables congestion monitoring.
switch(config-profile)# no tcp cwm
The following example leaves the CWM feature in an enabled state but changes the burstsize to the
default of 10 KB.
switch(config-profile)# no tcp cwm burstsize 25
tcp keepalive-timeout
To configure the interval between which the TCP connection verifies if the FCIP link is functioning, use the tcp keepalive-timeout command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp keepalive-timeout seconds
no tcp keepalive-timeout seconds
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
keepalive-timeout
|
Specifies the keepalive timeout interval for the TCP connection.
|
seconds
|
Specifies the time in seconds.
|
Defaults
None.
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The default is 60 seconds. The range is from 1 to 7200 seconds.
This command can be used to detect FCIP link failures.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example specifies the keepalive timeout interval for the TCP connection:
switch(config-profile)# tcp keepalive-timeout 120
tcp maximum-bandwidth
To manage the window size, use the tcp maximum-bandwidth command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp max-bandwidth-mbps bandwidth min-available-bandwidth-mbps threshold
round-trip-time-ms milliseconds round-trip-time-us microeconds
no tcp max-bandwidth-mbps bandwidth min-available-bandwidth-mbps threshold
round-trip-time-ms seconds round-trip-time-us microeconds
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
max-bandwidth-mbps
|
Configures the maximum available end-to-end bandwidth in the path.
|
bandwidth
|
Specifies the Mbps bandwidth.
|
min-available-bandwidth-mbps
|
Configures the minimum slow start threshold.
|
threshold
|
Specifies the Mbps threshold.
|
round-trip-time-ms milliseconds
|
Configures the estimated round trip time across the IP network to reach the FCIP peer end point. in milliseconds
|
round-trip-time-us microeconds
|
Configures the estimated round trip time across the IP network to reach the FCIP peer end point. in microseconds
|
Defaults
Enabled.
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The maximum-bandwidth option and the round-trip-time option together determine the window size.
The minimum-available-bandwidth option and the round-trip-time option together determine the threshold below which TCP aggressively increases its size. After it reaches the threshold the software uses standard TCP rules to reach the maximum available bandwidth. The defaults are max-bandwidth = 1G, min-available-bandwidth = 2 Mbps, and round-trip-time is 10ms
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example configures the maximum available bandwidth at 900 Mbps, the minimum slow start threshold as 300 Mbps, and the round trip time as 10 milliseconds:
switch(config-profile)# tcp max-bandwidth-mbps 900 min-available-bandwidth-mbps 300
round-trip-time-ms 10
The following example reverts to the factory defaults. The defaults are max-bandwidth = 1G, min-available-bandwidth = 2 Mbps and round-trip-time is 10ms:
switch(config-profile)# no tcp max-bandwidth-mbps 900 min-available-bandwidth-mbps 300
round-trip-time-ms 10
The following example configures the maximum available bandwidth at 2000 Kbps, the minimum slow start threshold as 2000 Kbps, and the round trip time as 200 microseconds:
switch(config-profile)# tcp max-bandwidth-kbps 2000 min-available-bandwidth-kbps 2000
round-trip-time-us 200
tcp max-retransmissions
To specify the maximum number of times a packet is retransmitted before TCP decides to close the connection, use the tcp max-retransmissions command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp max-retransmissions number
no tcp max-retransmissions number
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
max-retransmissions
|
Configures the maximum number of retransmissions
|
number
|
Specifies the maximum number.
|
Defaults
Enabled
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The default is 4 and the range is from 1 to 8 retransmissions.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example specifies the maximum number of retransmissions :
switch(config-profile)# tcp max-retransmissions 6
tcp minimum-retransmit time
To control the minimum amount of time TCP waits before retransmitting, use the tcp minimum-retransmit-time command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp minimum-retransmit-time milliseconds
no tcp minimum-retransmit-time milliseconds
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
minimum-retransmit-time
|
Controls the retransmit time for the TCP connection.
|
milliseconds
|
Specifies the time in milliseconds.
|
Defaults
None.
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The default is 300 milliseconds and the range is from 250 to 5000 milliseconds.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example specifies the minimum TCP retransmit time for the TCP connection:
switch(config-profile)# tcp min-retransmit-time 500
tcp pmtu-enable
To configure path MTU (PMTU) discovery, use the tcp pmtu-enable command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp pmtu-enable [reset-timeout seconds ]
no tcp pmtu-enable [reset-timeout seconds ]
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
pmtu-enable
|
Configures PMTU discovery with the default value of 3600 seconds.
|
reset-timeout
|
Specifies the PMTU reset timeout.
|
seconds
|
Specifies the reset timeout seconds.
|
Defaults
Enabled
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The default is 3600 seconds and the range is from 60 to 3600 seconds.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example disables PMTU discovery:
switch(config-profile)# no tcp pmtu-enable
The following example enables PMTU discovery with a default of 3600 seconds:
switch(config-profile)# tcp pmtu-enable
The following example specifies the PMTU reset timeout to 90 seconds:
switch(config-profile)# tcp pmtu-enable reset-timeout 90
The following example leaves the PMTU in an enabled state but changes the timeout to the default of 3600 seconds:
switch(config-profile)# no tcp pmtu-enable reset-timeout 600
tcp qos control
To specify the differentiated services code point (DSCP) value to mark all IP packets (type of service—TOS field in the IP header), use the tcp qos control command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp qos control value data value
no tcp qos control value data value
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
qos control value
|
Applies the control DSCP value to all FCIP frames in the control TCP connection.
|
data value
|
Applies the data DSCP value applies to all FCIP frames in the data connection.
|
Defaults
Enabled
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
Use these TCP parameters to control TCP retransmission behavior in a switch.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example configures the control TCP connection and data connection to mark all packets on that DSCP value:
switch(config-profile)# tcp qos control 3 data 5
tcp sack-enable
To configure selective acknowledgment (SACK) to overcome the limitations of multiple lost packets during a TCP transmission, use the tcp command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp sack-enable burstsize
no tcp sack-enable burstsize
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
sack-enable
|
Configures the SACK mechanism.
|
Defaults
Enabled
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The receiving TCP sends back SACK advertisements to the sender. The sender can then retransmit only the missing data segments.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example enables the SACJ mechanism on the switch:
switch(config-profile)# tcp sack-enable
tcp send-buffer-size
To define the required additional buffering—beyond the normal send window size —that TCP allows before flow controlling the switch's egress path for the FCIP interface, use the tcp send-buffer-size command. Use the no form of this command to disable this feature or revert to its factory defaults.
tcp send-buffer-size buffer-size
no tcp send-buffer-size buffer-size
Syntax Description
tcp
|
Configures TCP parameters for the FCIP profile.
|
send-buffer-size
|
Defines required additional buffering allowed by TCP.
|
buffer-size
|
Specifies the buffer size in KB.
|
Defaults
Enabled
Command Modes
Configuration mode—fcip profile submode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
The default buffer size is 0 and the valid range is from 0 to 8192 KB.
Examples
The following example configures a FCIP profile:
switch(config)# fcip profile 5
The following example configure the advertised buffer size to 5000 KB :
switch(config-profile)# tcp send-buffer-size 5000
telnet
To log in to a host that supports Telnet, use the telnet command in EXEC mode.
telnet [hostname | ip-address]
Syntax Description
hostname
|
(Optional) Host name. Maximum length is 64 characters.
|
ip-address
|
(Optional) IP address Maximum length is 64 characters.
|
Defaults
None.
Command Modes
EXEC mode.
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
None.
Examples
The following example establishes a Telnet session to the specified IP address.
switch# telnet 172.22.91.153
Connected to 172.22.91.153.
telnet server enable
To enable the Telnet server if you wish to return to a Telnet connection from a secure SSH connection, use the telnet server enable command. To disable the Telnet server, use the no form of this command
telnet server enable
no telnet server enable
Syntax Description
This command has no arguments or keywords.
Defaults
Enabled.
Command Modes
Configuration mode.
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
None.
Examples
The following example enables the Telnet server.
switch(config)# telnet server enable
switch(config)# no telnet server enable
Related Commands
Command
|
Description
|
telnet
|
Logs in to a host that supports Telnet.
|
terminal
To configure terminal attributes, use the terminal command in EXEC mode. To stop the display of syslog output, use the no form of the command.
terminal [length number-of-lines | monitor | terminal-type | unlock | width integer]
Syntax Description
length
|
(Optional) Sets the number of lines on the screen.
|
number-of-lines
|
(Optional) Specifies the number of lines on the screen from 0 to 512. Enter 0 to scroll continuously.
|
monitor
|
(Optional) Displays syslog output for the current terminal and session.
|
terminal-type
|
(Optional) Sets the terminal type.
|
width
|
(Optional) Sets the width of the display terminal, from 0 to 80.
|
integer
|
Sets the width of the display terminal, from 0 to 80.
|
Defaults
The default number of lines for the length is 24. The default width is 80 lines.
Command Modes
EXEC
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
Remember that all terminal parameter-setting commands are set locally and do not remain in effect after a session is ended. You must perform this task at the EXEC prompt at each session to see the debugging messages.
If the length is not 24 and the width is not 80, then you need to set a length and width.
Examples
The following example displays debug command output and error messages during the current terminal session.
Aug 8 10:32:42 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_CFG_PWRDN: Module 1 powered down
Aug 8 10:32:42 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_PWRDN: Module 1 powered down
Aug 8 10:32:42 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_INSERT: Module 1 has been inserted
Aug 8 10:33:12 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_PWRON: Module 1 powered up
Aug 8 10:33:13 sup48 % LOG_MODULE-5-MOD_REG_OK: LCM - Registration succeeded for module 1
Aug 8 10:38:15 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_CFG_PWRDN: Module 1 powered down
Aug 8 10:38:15 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_INSERT: Module 1 has been inserted
Aug 8 10:38:45 sup48 % LOG_MODULE-5-MOD_REG_OK: LCM - Registration succeeded for module 1
Aug 8 10:43:10 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_CFG_PWRDN: Module 1 powered down
Aug 8 10:43:10 sup48 % LOG_PLATFORM-5-PLATFORM_MOD_PWRDN: Module 1 powered down
The following example stops the current terminal monitoring session.
switch# terminal no monitor
time-stamp
To enable FCIP time stamps on a frame, use the time-stamp option. To disable this option for the selected interface, use the no form of the option.
time-stamp | acceptable-diff number
no time-stamp | acceptable-diff number
Syntax Description
time-stamp
|
Configures time-stamp.
|
acceptable-diff
|
Configures the acceptable time difference for time-stamps.
|
number
|
Enters the acceptable time from 1 to 60000.
|
Defaults
Disabled.
Command Modes
Configuration mode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.1(1).
Usage Guidelines
Access this command from the switch(config-if)# submode.
The time-stamp option instructs the switch to discard frames that are older than a specified time.
Examples
switch(config)# interface fcip 50
switch(config-if)# time-stamp
switch(config-if)# time-stamp acceptable-diff 4000
Related Commands
Command
|
Description
|
show interface fcip
|
Displays an interface configuration for a specified FCIP interface.
|
traceroute
To print the route an IP packet takes to a network host, use the traceroute command in EXEC mode.
traceroute {hostname | ip-address}
Syntax Description
host name
|
The host name.
|
ip-address
|
The IP address.
|
Defaults
None.
Command Modes
EXEC mode.
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
This command traces the route an IP packet follows to an internet host by launching UDP probe packets with a small TTL (time to live) then listening for an ICMP (Internet Control Message Protocol) "time exceeded" reply from a gateway.
Note Probes start with a TTL of one and increase by one until encountering an ICMP "port unreachable." This means that the host was accessed or a maximum flag was hit. A line is printed showing the TTL, address of the gateway and round trip time of each probe. If the probe answers come from different gateways, the address of each responding system is printed.
Examples
The following example prints the route IP packets take to the network host www.cisco.com.
switch# traceroute www.cisco.com
traceroute to www.cisco.com (171.71.181.19), 30 hops max, 38 byte packets
1 kingfisher1-92.cisco.com (172.22.92.2) 0.598 ms 0.470 ms 0.484 ms
2 nubulab-gw1-bldg6.cisco.com (171.71.20.130) 0.698 ms 0.452 ms 0.481 ms
3 172.24.109.185 (172.24.109.185) 0.478 ms 0.459 ms 0.484 ms
4 sjc12-lab4-gw2.cisco.com (172.24.111.213) 0.529 ms 0.577 ms 0.480 ms
5 sjc5-sbb4-gw1.cisco.com (171.71.241.174) 0.521 ms 0.495 ms 0.604 ms
6 sjc12-dc2-gw2.cisco.com (171.71.241.230) 0.521 ms 0.614 ms 0.479 ms
7 sjc12-dc2-cec-css1.cisco.com (171.71.181.5) 2.612 ms 2.093 ms 2.118 ms
8 www.cisco.com (171.71.181.19) 2.496 ms * 2.135 ms
trunk protocol enable
To configure the trunk protocol, use the trunk protocol enable command in configuration mode. To disable the trunk protocol, use the no form of the command.
trunk protocol enable
no trunk protocol enable
Syntax Description
This command has no other arguments or keywords.
Command Modes
Configuration mode
Command History
This command was introduced in Cisco MDS SAN-OS Release 1.0(2).
Usage Guidelines
If the trunking protocol is disabled on a switch, no port on that switch can apply new trunk configurations. Existing trunk configurations are not affected—the TE port continues to function in trunking mode, but only supports traffic in VSANs that it negotiated previously (when the trunking protocol was enabled). Also, other switches that are directly connected to this switch are similarly affected on the connected interfaces. In some cases, you may need to merge traffic from different port VSANs across a non-trunking ISL. If so, you need to disable the trunking protocol.
Examples
The following example shows how to enable and disable the trunk protocol feature.
switch(config)# trunk protocol enable
switch(config)# no trunk protocol enable