|
|
Use the set ntp server command to configure the IP address of the NTP server.
set ntp server ip_addr
ip_addr | IP address of the NTP server providing the clock synchronization. |
This command has no default setting.
Switch command.
Privileged.
The client mode assumes that the client (the Catalyst 6000 or 6500 series switch) sends time-of-day requests regularly to the NTP server. A maximum of ten servers per client is allowed.
This example shows how to configure an NTP server:
Console> (enable) set ntp server 172.20.22.191 NTP server 172.20.22.191 added. Console> (enable)
Use the set password command to change the login password on the CLI.
set passwordThis command has no arguments or keywords.
The default is no password is configured.
Switch command.
Privileged.
The command prompts you for the old password. If the password you enter is valid, you are prompted to enter a new password and to verify the new password. A zero-length password is allowed by pressing Return.
This example shows how to set an initial password:
Console> (enable) set password Enter old password: <old_password> Enter new password: <new_password> Retype new password: <new_password> Password changed. Console> (enable)
Use the set port broadcast command to set the broadcast suppression for one or more ports. The broadcast threshold limits the backplane traffic received from the module.
set port broadcast mod_num/port_num threshold%
mod _num | Number of the module. |
port_num | Number of the port. |
threshold% | Percentage of total available bandwidth that can be used by broadcast traffic. |
The default is broadcast suppression disabled (no broadcast limit).
Switch command.
Privileged.
This example shows how to limit broadcast traffic to 20 percent to all ports on module 4:
Console> (enable)set port broadcast 4/3 20%Port 4/1-24 broadcast traffic limited to 20%.Console> (enable)
This example shows how to allow unlimited broadcast traffic to all ports on module 4:
Console> (enable)set port broadcast 4/3 100%Port 4/1-24 broadcast traffic unlimited.Console> (enable)
clear port broadcast
show port broadcast
Use the set port channel command to configure EtherChannel on Ethernet module ports.
set port channel mod/ports... [admin_group]
mod/ports... | Number of module and port(s). |
admin_group | (Optional) Number of administrative group. Valid values are 1 to 1024. |
mod_num/port_num | Number of module and port(s). |
mode | Keyword to specify the EtherChannel mode. |
on | (Optional) Keyword to enable and force specified ports to channel without PAgP. |
off | (Optional) Keyword to prevent ports from channeling. |
desirable | (Optional) Keyword to set a PAgP mode that places a port into an active negotiating state, in which the port initiates negotiations with other ports by sending PAgP packets. |
auto | (Optional) Keyword to set a PAgP mode that places a port into a passive negotiating state, in which the port responds to PAgP packets it receives, but does not initiate PAgP packet negotiation. |
silent | (Optional) Keyword to use with auto or desirable when no traffic is expected from the other device to prevent the link from being reported to STP as down. |
non-silent | (Optional) Keyword to use with auto or desirable when traffic is expected from the other device. |
all distribution | Keyword to apply frame distribution to all ports in the switch. |
ip | Keyword to specify the frame distribution method using IP address values. |
mac | Keyword to specify the frame distribution method using MAC address values. |
source | (Optional) Keyword to specify the frame distribution method using source address values. |
destination | (Optional) Keyword to specify the frame distribution method using destination address values. |
both | (Optional) Keyword to specify the frame distribution method using source and destination address values. |
The default is EtherChannel is set to auto and silent on all module ports. The defaults for frame distribution are ip and both.
Switch command.
Privileged.
Make sure that all ports in the channel are configured with the same port speed, duplex mode, and so forth. For more information on EtherChannel, refer to the Software Configuration Guide for your switch.
With the on mode, a usable EtherChannel exists only when a port group in on mode is connected to another port group in on mode.
If you are running QoS, make sure that bundled ports are all of the same trust types and have similar queueing and drop capabilities.
Disable the port security feature on the channeled ports (see the set port security command). If you enable port security for a channeled port, the port shuts down when it receives packets with source addresses that do not match the secure address of the port.
You can configure up to eight ports on the same switch in each administrative group.
When you assign ports to an existing admin group, the original ports associated with the admin group will be moved to an automatically picked new admin group. You cannot add ports to the same admin group.
If you do not enter an admin_group, it means that you want to create a new administrative group with admin_group selected automatically. The next available admin_group is automatically selected.
If you do not enter the channel mode, the channel mode of the ports addressed are not modified.
The silent | non-silent parameters only apply if desirable or auto modes are entered.
If you do not specify silent or non-silent, the current setting is not affected.
This command is not supported by non-EtherChannel-capable modules.
This example shows how to set the channel mode to desirable:
Console> (enable) set port channel 2/2-8 mode desirable Ports 2/2-8 channel mode set to desirable.
This example shows how to set the channel mode to auto:
Console> (enable) set port channel 2/7-8,3/1 mode auto Ports 2/7-8,3/1 channel mode set to auto. Console> (enable)
This example shows how to group ports 4/1-4 in an admin group:
Console> (enable) set port channel 4/1-4 96
Port(s) 4/1-4 are assigned to admin group 96.
Console> (enable)
This example shows the display when the port list is exceeded:
Console> (enable) set port channel 2/1-9 1 No more than 8 ports can be assigned to an admin group. Console> (enable)
This example shows how to disable EtherChannel on module 4, ports 4 through 6:
Console> (enable)set port channel 4/4-6 mode offPort(s) 4/4-6 channel mode set to off.Console> (enable)
This example shows the display output when you assign ports to an existing admin group. This example moves ports in admin group 96 to another admin group and assigns ports 4/4-6 to admin group 96:
Console> (enable)set port channel 4/4-6 96Port(s) 4/1-3 are moved to admin group 97.Port(s) 4/4-6 are assigned to admin group 96.Console> (enable)
This example shows how to set the channel mode to off for ports 4/4-6 and assign ports 4/4-6 to an automatically selected admin group:
Console> (enable)set port channel 4/4-6 offPort(s) 4/4-6 channel mode set to off.Port(s) 4/4-6 are assigned to admin group 23.Console> (enable)
This example shows how to configure the EtherChannel load-balancing feature:
Console> (enable)set port channel all distribution ip destChannel distribution is set to ip destination.Console> (enable)
show port channel
show channel
show channel group
Use the set port disable command to disable a port or a range of ports.
set port disable mod_num/port_num
mod _num | Number of the module. |
port_num | Number of the port. |
The default system configuration has all ports enabled.
Switch command.
Privileged.
This example shows how to disable a port using the set port disable command:
Console> (enable) set port disable 5/10 Port 5/10 disabled. Console> (enable)
Use the set port duplex command to configure the duplex type of an Ethernet port or a range of ports.
set port duplex mod_num/port_num {full | half | auto}
mod_num | Number of the module. |
port_num | Number of the port. |
full | Keyword to specify full-duplex transmission. |
half | Keyword to specify half-duplex transmission. |
auto | Keyword to specify auto transmission. |
The default is that the duplex type is set to auto.
Switch command.
Privileged.
When a port is in autosensing mode, both its speed and duplex are determined by autosensing. An error message like the following is generated if you attempt to set the transmission type of autosensing Ethernet ports to half- or full-duplex mode:
Console> (enable) set port duplex 2/1 full (1 port - failed)
Port 2/1 is in auto-sensing mode. Console> (enable)
Gigabit ports only support full-duplex mode.
This example shows how to set port 1 on module 2 to full duplex:
Console> (enable) set port duplex 2/1 full Port 2/1 set to full-duplex. Console> (enable)
Use the set port enable command to enable a port or a range of ports.
set port enable mod_num/port_num
mod _num | Number of the module. |
port_num | Number of the port. |
The default is all ports are enabled.
Switch command.
Privileged.
This example shows how to enable port 3 on module 2:
Console> (enable) set port enable 2/3 Port 2/3 enabled. Console> (enable)
Use the set port flowcontrol command to set the receive flow-control value for a particular EtherChannel switching module port.
set port flowcontrol {mod_num/port_num} {receive | send} {off | on | desired}
mod_num | Number of the module. |
port_num | Number of the port on the module. |
receive | Keyword to indicate whether the port can receive administrative status from a remote device. |
send | Keyword to indicate whether the local port can send administrative status to a remote device. |
off | Keyword, when used with receive, to turn off an attached device's ability to send flow-control packets to a local port. When used with send, turns off the local port's ability to send administrative status to a remote device. |
on | Keyword, when used with receive, to require that a local port receive administrative status from a remote device. When used with send, the local port sends administrative status to a remote device. |
desired | Keyword, when used with receive, to allow a local port to operate with an attached device that is required to send flow-control packets, or with an attached device that is not required to but may send flow-control packets. When used with send, the local port sends administrative status to a remote device if the remote device supports it. |
The default is off for receive and desired for send except for the 24-port 100BaseFX and 48-port 10/100 BaseTX RJ-45 modules; the default is off for receive and off for send.
Switch command.
Privileged.
When you configure the the 24-port 100BaseFX and 48-port 10/100 BaseTX RJ-45 modules, you can only set the receive flow control to on or off and the send flow control to off.
These examples show how to use the set port flowcontrol command set:
Console> (enable) set port flowcontrol 5/1 receive on Port 5/1 flow control receive administration status set to on (port will require far end to send flowcontrol) Console> (enable) Console> (enable) set port flowcontrol 5/1 receive desired Port 5/1 flow control receive administration status set to desired (port will allow far end to send flowcontrol if far end supports it) Console> (enable) Console> (enable) set port flowcontrol 5/1 receive off Port 5/1 flow control receive administration status set to off (port will not allow far end to send flowcontrol) Console> (enable) Console> (enable) set port flowcontrol 5/1 send on Port 5/1 flow control send administration status set to on (port will send flowcontrol to far end) Console> (enable) Console> (enable) set port flowcontrol 5/1 send desired Port 5/1 flow control send administration status set to desired (port will send flowcontrol to far end if far end supports it) Console> (enable) Console> (enable) set port flowcontrol 5/1 send off Port 5/1 flow control send administration status set to off (port will not send flowcontrol to far end) Console> (enable)
Use the set port gmrp command to enable or disable GMRP on the specified ports in all VLANs.
set port gmrp {mod/ports...} {enable | disable}
mod/ports... | Module number and port number list. |
enable | Keyword to enable GVRP on a specifed port. |
disable | Keyword to disable GVRP on a specifed port. |
The default is GMRP is disabled.
Switch command.
Privileged.
You can enter this command even when GMRP is not enabled, but the values come into effect only when GMRP is enabled using the set gmrp enable command.
This example shows how to enable GMRP on module 3, port 1:
Console> (enable) set port gmrp 3/1 enable GMRP enabled on port(s) 3/1. GMRP feature is currently disabled on the switch. Console> (enable)
This example shows how to disable GMRP on module 3, ports 1 through 5:
Console> (enable) set port gmrp 3/1-5 disable GMRP disabled on port(s) 3/1-5. Console> (enable)
Use the set port gvrp command to enable or disable GVRP on the specified ports in all VLANs.
set port gvrp {mod/ports...} {enable | disable}
mod/ports... | Module number and port number list. |
enable | Keyword to enable GVRP on a specifed port. |
disable | Keyword to disable GVRP on a specifed port. |
The default is GVRP is disabled.
Switch command.
Privileged.
When VTP pruning is enabled, VTP pruning runs on all the GVRP-disabled trunks.
To run GVRP on a trunk, GVRP needs to be enabled both globally on the switch and enabled individually on the trunk.
You can configure GVRP on a port even when GVRP is globally disabled. However, the port will not become a GVRP participant until GVRP is also globally enabled.
GVRP can only be enabled on an 802.1Q trunk.
If you enter the command without specifying the port number, GVRP is affected globally in the switch.
This example shows how to enable GVRP on module 3, port 2:
Console> (enable) set port gvrp 3/2 enable GVRP enabled on 3/2. Console> (enable)
This example shows how to disable GVRP on module 3, port 2:
Console> (enable) set port gvrp 3/2 disable GVRP disabled on 3/2. Console> (enable)
This example shows what happens if you try to enable GVRP on a port that is not an 802.1Q trunk:
Console> (enable) set port gvrp 4/1 enable Failed to set port 4/1 to GVRP enable. Port not allow GVRP. Console> (enable)
This example shows what happens if you try to enable GVRP on a specific port when GVRP has not first been enabled using the set gvrp command:
Console> (enable) set port gvrp 5/1 enableGVRP enabled on port(s) 5/1.GVRP feature is currently disabled on the switch.Console> (enable)
show gvrp configuration
set gvrp
clear gvrp statistics
Use the set port name command to configure a name for a port.
set port name mod_num/port_num [port_name]
mod_num | Number of the module. |
port_num | Number of the port. |
port_name | (Optional) String that describes the port. |
The default configuration has no port name configured for any port.
Switch command.
Privileged.
If you do not specify the name_string, the port name is cleared.
This example shows how to set port 1 on module 4 to Snowy:
Console> (enable) set port name 4/1 Snowy Port 4/1 name set. Console> (enable)
set port disable
set port duplex
set port enable
set port speed
set port trap
show port
Use the set port negotiation command to enable or disable the link negotiation protocol on the specified port.
set port negotiation mod_num/port_num {enable | disable}
mod_num | Number of the module. |
port_num | Number of the port. |
enable | Keyword to enable the link negotiation protocol. |
disable | Keyword to disable the link negotiation protocol. |
The default is link negotiation protocol enabled.
Switch command.
Privileged.
This command only applies to ports on the Gigabit Ethernet switching module.
This example shows how to disable link negotiation protocol on port 1, module 4:
Console> (enable) set port negotiation 4/1 disable Link negotiation protocol disabled on port 4/1. Console> (enable)
Use the set port protocol command to enable or disable protocol membership of ports.
set port protocol mod_num/port_num {ip | ipx | group} {on | off | auto}
mod_num | Number of the module. |
port_num | Number of the port. |
ip | Keyword to specify IP protocol. |
ipx | Keyword to specify Internetwork Packet Exchange protocol. |
group | Keyword to specify VINES, AppleTalk, and DECnet protocols. |
on | Keyword to indicate the port will receive all the flood traffic for that protocol. |
off | Keyword to indicate the port will not receive any flood traffic for that protocol. |
auto | Keyword to indicate the port will not receive any flood traffic for that protocol. |
The default is that the ports are configured to on for the IP protocol groups and auto for IPX and group protocols.
Switch command.
Privileged.
Protocol filtering is supported only on nontrunking EtherChannel ports. Trunking ports are always members of all the protocol groups.
If the port configuration is set to auto, the port initially does not receive any flood packets for that protocol. When the corresponding protocol packets are received on that port, the supervisor engine detects this and adds the port to the protocol group.
Ports configured as auto are removed from the protocol group if no packets are received for that protocol within a certain period of time. This aging time is set to 60 minutes. They are also removed from the protocol group on detection of a link down.
This example shows how to disable IPX protocol membership of port 1 on module 2:
Console> (enable) set port protocol 2/1 ipx off IPX protocol disabled on port 2/1. Console> (enable)
This example shows how to enable automatic IP membership of port 1 on module 5:
Console> (enable) set port protocol 5/1 ip auto IP protocol set to auto mode on module 5/1. Console> (enable)
Use the set port qos cos command to set the value for all packets that have arrived through an untrusted port.
set port qos mod/ports.. cos cos_value
mod/ports.. | Number of the module and the port(s). |
cos-value | CoS value; valid values are 0 through 7. |
The default CoS on all ports is 0.
Switch command.
Privileged.
This example shows how to set the default value on a port:
Console> (enable)set port qos 2/1 cos 3Port 2/1 qos cos set to 3Console> (enable)
clear port qos cos
show qos info
Use the set port qos trust command to set the trusted state of a port, for example, whether the packets arriving at a port are trusted to carry the correct classification.
set port qos mod/ports.. trust {untrusted | trust-cos}
mod/ports.. | Number of the module and the port(s). |
untrusted | Keyword to specify that the CoS bits in the incoming packets need to be reclassified. |
trust-cos | Keyword to specify that although the CoS bits in the incoming packets are trusted, the ToS is invalid and a valid value needs to be derived from the CoS bits. |
The default is all ports are untrusted, and the default CoS set on the port is forced on all the ingress packets.
Switch command.
Privileged.
This example shows how to set the trusted state of a module:
Console> (enable)set port qos 3/7 trust trust-cosPort 3/7 qos set to trust-cosConsole> (enable)
Use the set port security command to configure port security on a port or range of ports.
set port security mod_num/port_num {enable | disable} [mac_addr]
mod_num | Number of the module. |
port_num | Number of the port. |
enable | Keyword to enable port security. |
disable | Keyword to disable port security. |
mac_addr | (Optional) Secure MAC address of the enabled port. |
The default configuration has port security disabled.
Switch command.
Privileged.
If the MAC address is not given, the command turns on learning mode so that the first MAC address seen on the port becomes the secure MAC address.
This command is supported on all Ethernet modules.
This example shows how to set port security with a learned MAC address:
Console> (enable)set port security 3/1 enablePort 3/1 port security enabled with the learned mac address.Console> (enable)
This example shows how to set port security with a specific MAC address:
Console> (enable)set port security 3/1 enable 01-02-03-04-05-06Port 3/1 port security enabled with 01-02-03-04-05-06 as the secure mac address.Console> (enable)
Use the set port speed command to configure the speed of a port interface. You can configure the speed of a Fast Ethernet interface.
set port speed mod_num/port_num {10 | 100 | auto}
mod_num | Number of the module. |
port_num | Number of the port on the module. |
10 | 100 | auto | Keyword to set a port speed to 10 Mbps, 100 Mbps, or autospeed detection mode. |
The default is all module ports are set to auto.
Switch command.
Privileged.
You can configure Fast Ethernet interfaces on the 10/100-Mbps Fast Ethernet switching module to either 10 Mbps or 100 Mbps, or set to autosensing mode, allowing them to sense and distinguish between 10-Mbps and 100-Mbps port transmission speeds and full-duplex or half-duplex port transmission types at a remote port connection. If you set the interfaces to autosensing, they configure themselves automatically to operate at the proper speed and transmission type.
This command is not supported by the Gigabit Ethernet switching module.
This example shows how to configure port 1 on module 2 to auto:
Console> (enable) set port speed 2/1 auto Port 2/1 speed set to auto-sensing mode. Console> (enable)
This example shows how to configure port 2 on module 2 port speed to 10 Mbps:
Console> (enable) set port speed 2/2 10 Port 2/2 speed set to 10 Mbps. Console> (enable)
set port disable
set port enable
set port name
set port trap
show port
Use the set port trap command to enable or disable the operation of the standard SNMP link trap (up or down) for a port or range of ports.
set port trap mod_num/port_num {enable | disable}
mod_num | Number of the module. |
port_num | Number of the port. |
enable | Keyword to activate the SNMP link trap. |
disable | Keyword to deactivate the SNMP link trap. |
The default is all port traps are disabled.
Switch command.
Privileged.
This example shows how to enable the SNMP link trap for module 1, port 2:
Console> (enable) set port trap 1/2 enable Port 1/2 up/down trap enabled. Console> (enable)
set port disable
set port duplex
set port enable
set port name
set port speed
show port
Use the set power redundancy command to turn redundancy between the power supplies on or off.
set power redundancy enable | disable
enable | Keyword to activate redundancy between the power supplies. |
disable | Keyword to deactivate redundancy between the power supplies. |
The default is power redundancy is disabled.
Switch command.
Privileged.
In a system with dual power supplies, this command turns redundancy between the power supplies on or off. In a redundant configuration, the power available to the system is the maximum power capability of the weakest supply.
In a nonredundant configuration, the power available to the system is the sum of the power capability of both supplies.
This example shows how to activate redundancy between power supplies:
Console> (enable) set power redundancy enable Power supply redundancy enabled.
This example shows how to deactivate redundancy between power supplies:
Console> (enable) set power redundancy disable Power supply redundancy disabled. Console> (enable)
Use the set prompt command to change the prompt for the CLI.
set prompt prompt_string
prompt_string | String to use as the command prompt. |
The default is the prompt is set to Console>.
Switch command.
Privileged.
If you use the set system name command to assign a name to the switch, the switch name is used as the prompt string. However, if you specify a different prompt string using the set prompt command, that string is used for the prompt.
This example shows how to set the prompt to system100>:
Console> (enable) set prompt system100> system100> (enable)
Use the set protocolfilter command to activate or deactivate protocol filtering on Ethernet VLANs and on nontrunking Ethernet, Fast Ethernet, and Gigabit Ethernet ports.
set protocolfilter {enable | disable}
enable | Keyword to activate protocol filtering. |
disable | Keyword to deactivate protocol filtering. |
The default is protocol filtering is disabled.
Switch command.
Privileged.
Protocol filtering is supported only on Ethernet VLANs and on nontrunking EtherChannel ports.
This example shows how to activate protocol filtering:
Console> (enable) set protocolfilter enable Protocol filtering enabled on this switch. Console> (enable)
This example shows how to deactivate protocol filtering:
Console> (enable) set protocolfilter disable Protocol filtering disabled on this switch. Console> (enable)
Use the set qos command to turn on or turn off QoS functionality on the switch.
set qos enable | disable
enable | Keyword to activate QoS functionality. |
disable | Keyword to deactivate QoS functionality. |
The default is QoS functionality is disabled. Refer to Table 2-1 for the QoS default settings.
Switch command.
Privileged.
You can change the QoS default configuration. Refer to the Catalyst 6000 and 6500 Series Software Configuration Guide for additional information.
When QoS is enabled and disabled in quick succession (within 2 seconds of each other), the ports may go through a line up and down due to a modification of the txq-ratio size and you might receive a bus timeout.
This example shows how to enable QoS:
Console> (enable)set qos enable<...trunking reset messages deleted ...>QoS is enabled.Console> (enable)
This example shows how to disable QoS:
Console> (enable)set qos disable<...trunking reset messages deleted ...>QoS is disabled.Console> (enable)
Use the set qos drop-threshold command to program the transmit and receive drop thresholds on all ports in the system.
set qos drop-threshold 2q2t tx queue q# thr1 thr2
2q2t tx | Keyword used to specify the transmit drop threshold. |
1q4t rx | Keyword used to specify the receive drop threshold. |
queue | Keyword used to specify the queue. |
q# | Number of the queue. Valid values are 1 and 2. |
thr1, thr2, thr3, thr4 | Threshold percentage. Valid values are 1 to 100. |
If QoS is enabled, the following defaults apply:
If QoS is disabled, the following defaults apply:
Switch command.
Privileged.
The number preceding the t letter in the port_type (2q2 or 1q4t) determines the number of threshold values the hardware supports. For example, with 2q2t, the number of thresholds specified is two; with 1q4t, the number of thresholds specified is four.
The number preceding the q letter in the port_type determines the number of the queues that the hardware supports. For example, with 2q2t, the number of queues specified is two; with 1q4t, the number of queues specified is four.
The thresholds are all specified as percentages. 10 indicates a threshold when the buffer is 10 percent full.
Due to the granularity of programming the hardware, the values set in hardware will be close approximations of the values provided.
The system defaults for the transmit queues attempt to keep the maximum latency through a port at a maximum of 10 msec.
This example shows how to assign the transmit drop threshold:
Console> (enable) set qos drop-threshold 2q2t tx queue 1 40 80 Transmit drop thresholds for queue 1 set at 40% and 80% Console> (enable)
This example shows how to assign the receive drop threshold:
Console> (enable)set qos drop-threshold 1q4t rx queue 1 40 50 60 100Receive drop thresholds for queue 1 set at 40% 50% 60% 100%Console> (enable)
Use the set qos mac-cos command to set the CoS value to the MAC address and VLAN pair.
set qos mac-cos dest_mac vlan cos
dest_mac | MAC address of the destination host. |
vlan | Number of the VLAN; valid values are 1 to 1001. |
cos | CoS value; valid values are 0 to 7, with the higher numbers representing higher priority. |
This command has no default setting.
Switch command.
Privileged.
The set qos mac-cos command creates a permanent CAM entry that remains in the CAM table until the active supervisor is reset.
The port associated with the MAC address is learned when the first packet with this source MAC address is received. These entries are not aged out.
The CoS for a packet going to the specified MAC address is overwritten even if it is coming from a trusted port.
If you enter the show cam command, entries made with the set qos mac-cos command are displayed as dynamic because QoS considers them to be dynamic, but they do not age out.
This example shows how to assign the CoS value 3 to VLAN 2:
Console> (enable)set qos mac-cos 0f-ab-12-12-00-13 2 3CoS 3 is assigned to 0f-ab-12-12-00-13 vlan 2.Console> (enable)
clear qos mac-cos
show qos mac-cos
Use the set qos map command to map a specific CoS value to one of the two transmit priority queues and one of the two thresholds per available priority queue for all ports.
set qos map port_type q# thr# cos coslist
port_type | Only valid value for port_type is 2q2t. The same mapping is used for both the receive and transmit directions. |
q# | Value determined by the number of priority queues provided at the transmit end. Valid values are 1 and 2, with the higher value indicating a higher priority queue. |
thr# | Value determined by the number of drop thresholds available at a port. Valid values are 1 and 2, with the higher value indicating lower chances of being dropped. |
cos | Keyword used to specify CoS values. |
coslist | List of CoS values between 0-7, with the higher numbers representing higher priority. |
The default mappings for all ports are shown in Table 2-2 and Table 2-3.
Switch command.
Privileged.
This example shows how to assign the CoS values 1, 2, and 5 to the first queue and the first drop threshold in that queue:
Console> (enable) set qos map 2q2t 1 1 cos 1,2,5
Qos tx priority queue and threshold mapped to cos successfully.
Console> (enable)
This example shows how to assign the CoS values to queue 1 and threshold 2 in that queue:
Console> (enable) set qos map 2q2t 1 2 cos 3-4,7
Qos tx priority queue and threshold mapped to cos successfully.
Console> (enable)
Use the set qos txq-ratio command to set the amount of packet buffer memory allocated to high-priority traffic and low-priority traffic.
set qos txq-ratio port_type queue1_val queue2_val
port_type | Only valid value for port_type is 2q2t. |
queue1_val | Percentage of low-priority traffic. Valid values are 1 to 99 and must total 100 with the queue2_val value. |
queue2_val | Percentage of high-priority traffic. Valid values are 1 to 99 and must total 100 with the queue1_val value. |
The default is 80:20 if QoS is enabled; 100:0 if QoS is disabled.
Switch command.
Privileged.
Use caution when using this command. When entering the set qos txq-ratio command, all ports will go through a link up and down condition.
Due to the granularity of programming the hardware, the values set in hardware will be close approximations of the values provided. For example, even if you specify 0 percent, the actual value programmed will not necessarily be 0.
The txq ratio is determined by the traffic mix in the network. Since high-priority traffic is typically a smaller fraction of the traffic and since the high-priority queue gets more service, the high-priority queue should be set lower than the low-priority queue.
This example shows how to allocate 75 percent of the packet buffer memory to low-priority traffic and 25 percent to high-priority traffic:
Console> (enable) set qos txq-ratio2q2t 75 25
QoS txq-ratio is set successfully.
Console> (enable)
Use the set qos wrr command to specify the weights used to determine how many packets will be transmitted out of one queue before switching to the other queue.
set qos wrr port_type queue1_val queue2_val
port_type | Only valid value for port_type is 2q2t. |
queue1_val | Number of weight for queue 1 and queue 2. Valid values are 1 to 255. |
The defaults are queue1_val=100, queue2_val=255.
Switch command.
Privileged.
The WRR weights are used to partition the bandwidth between the queues in the event all queues are nonempty. For example, weights of 1:3 mean that one queue gets 25 percent of the bandwidth and the other gets 75 percent as long as both queues have data.
The weights 1:3 do not necessarily lead to the same results as when the weights are 10:30. In the latter case, more data is serviced from each queue and hence the latency of packets being serviced from the other queue go up. Normally, for best results, set the weights up such that at least one packet (maximum size) can be serviced from the lower priority queue at a time. For the higher priority queue, set the weight such that multiple packets are serviced at any one time.
Due to the granularity of programming the hardware, the values set in hardware will be close approximations of the values provided. For example, even if you specify 0 percent, the actual value programmed will not necessarily be 0. Whatever weights you choose, choose them such that the resulting byte values programmed (refer to the show qos info runtime command) is at least equal to the MTU size.
In software release 5.2, the ratio achieved is only an approximation of what you specify since the cutoff is on a packet and midway through a packet. For example, if you specify that the ratio services 1000 bytes out of the low-priority queue, and there is a 1500-byte packet in the low-priority queue, the entire 1500-byte packet is transmitted because the hardware services an entire packet.
This example shows how to specify the weights for queue 1 and queue 2 to 30 and 70.
Console> (enable) set qos wrr 2q2t 30 70
QoS wrr ratio is set successfully.
Console> (enable)
show qos info
show qos statistics
Posted: Mon May 17 11:28:16 PDT 1999
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