Dell Networking S6000 System, Справочное руководство

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When a port receives traffic at a higher rate than it can process, the frames are
stored in the port buffer. As a result, buffer usage increases. When the buffer usage
reaches the value specified in the “pause-threshold” argument, the port sends
PAUSE frame to the connected link partner to stop sending the traffic. Eventually
this reduces the buffer usage. When the buffer usage drops by the value specified
in the “resume-threshold”, the port again sends a PAUSE frame with 0 as wait-time.
This results in resume of the paused traffic flow.
Important Points to Remember
• Do not enable
tx pause
when buffer carving is enabled. For information and
assistance, consult Dell Networking TAC.
• The only configuration applicable to half duplex ports is
rx off tx off
. The
following error is returned:
Can’t configure flowcontrol when half duplex is configure,
config ignored
• Half duplex cannot be configured when the flow control configuration is on
(default is
rx on tx on
). The following error is returned:
Can’t configure half duplex when flowcontrol is on, config
ignored
NOTE: The flow control must be off (
rx off tx off
) before configuring the
half duplex.
• Speeds less than 1 Gig cannot be configured when the asymmetric flow control
configuration is on. The following error is returned:
Can’t configure speed <1G when Asymmetric flowcontrol is on,
config ignored
• Dell Networking OS only supports
rx on tx on
and
rx off tx off
for
speeds less than 1 Gig (Symmetric).
NOTE: If you use the
disable rx flow control
command, Dell
Networking recommends rebooting the system.
Example
Dell(conf-if-Tegi-0/1)#show config
!
interface GigabitEthernet 0/1
no ip address
switchport
no negotiation auto
flowcontrol rx off tx on
no shutdown
...
Example
(Values)
This Example shows how Dell Networking OS negotiates the flow control values
between two Dell Networking chassis connected back-to-back using 1G copper
ports.
Configured
LocRxConf LocTxConf RemoteRxConf RemoteTxConf
off off off off
off on
on off
Interfaces
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