many out discards on one port - 5406zl - J8697A

[M.Breitenbach]

hello

we have a connection between 2 locations.

On both sides we have Procurve 5606 zl Switches.

Between the locations we have 100 Mbit

Both sides configured a trunk - same VLAN IDs / tagging etc.

On one switch we got many out discards ( 60 to 600 per second )

At first we changed the port and cable and set flow control disabled.

Both ports configured 100 Fdx

Nothing changed - new port in a new module - same.

We didnt have this on any other ports on these switches or on switches connected to

any idea what i can do ?

[Vince_Whirlwind]

give us a

   show run int

and a

   show int brief

for each of the connecting interfaces.

[M.Breitenbach]

hello,

show run int doesnt work...

i only got:

SWITCH(config)# show running-config
 status                Check if the running configuration differs from the
                       statup configuration.
 <cr>

show int brief:

B8 is the "problem" port

before we changed cable and port - we used A11.

                    | Intrusion                           MDI   Flow  Bcast
  Port      Type      | Alert     Enabled Status Mode       Mode  Ctrl  Limit
  --------- --------- + --------- ------- ------ ---------- ----- ----- ------
  A1-Trk6   100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  A2        100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  A3        100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  A4        100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  A5        100/1000T | No        Yes     Up     100HDx     MDIX  off   0
  A6        100/1000T | No        Yes     Up     100HDx     MDIX  off   0
  A7        100/1000T | No        Yes     Up     100FDx     MDIX  on    0
  A8        100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  A9        100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  A10       100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  A11-Trk10 100/1000T | No        Yes     Down   100FDx     MDI   off   0
  A12       100/1000T | No        Yes     Up     1000FDx    MDIX  on    0
  A13       100/1000T | No        Yes     Up     1000FDx    MDIX  on    0
  A14       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  A15       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  A16       100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  A17       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  A18       100/1000T | No        Yes     Down   1000FDx    Auto  off   0
  A19       100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  A20       100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  A21       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  A22       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  A23-Trk2  100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  A24-Trk2  100/1000T | No        Yes     Down   1000FDx    Auto  off   0
  B1-Trk6   100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  B2        100/1000T | No        Yes     Down   1000FDx    MDI   off   0
  B3        100/1000T | No        Yes     Up     100FDx     MDI   off   0
  B4-Trk33  100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  B5        100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B6        100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B7        100/1000T | No        Yes     Up     100FDx     MDI   on    0
  B8-Trk10  100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B9        100/1000T | No        Yes     Down   1000FDx    Auto  off   0
  B10       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B11       100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  B12       100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  B13       100/1000T | No        Yes     Up     100FDx     MDI   on    0
  B14       100/1000T | No        Yes     Down   100FDx     Auto  on    0
  B15       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B16       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B17       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B18       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B19       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B20       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  B21       100/1000T | No        Yes     Down   1000FDx    MDI   off   0

B22       100/1000T | No        Yes     Down   1000FDx    Auto  off   0
  B23       100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  B24-Trk19 100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  C1-Trk19  100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  C2        100/1000T | No        Yes     Up     100FDx     MDI   off   0
  C3        100/1000T | No        Yes     Down   1000FDx    MDIX  off   0
  C4        100/1000T | No        Yes     Up     1000FDx    MDIX  on    0
  C5        100/1000T | No        Yes     Down   1000FDx    MDI   off   0
  C6-Trk33  100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  C7        100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C8        100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C9        100/1000T | No        Yes     Up     1000FDx    MDIX  on    0
  C10       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C11       100/1000T | No        Yes     Up     1000FDx    MDIX  on    0
  C12       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C13       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  C14       100/1000T | No        Yes     Up     100FDx     MDI   off   0
  C15       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C16       100/1000T | No        Yes     Up     1000FDx    MDI   on    0
  C17       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  C18       100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  C19       100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  C20       100/1000T | No        Yes     Up     100FDx     MDIX  off   0
  C21-Trk19 100/1000T | No        Yes     Up     1000FDx    MDIX  off   0
  C22-Trk19 100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  C23-Trk2  100/1000T | No        Yes     Up     1000FDx    MDI   off   0
  C24-Trk2  100/1000T | No        Yes     Down   1000FDx    Auto  off   0

[Vince_Whirlwind]

You could upgrade your firmware, but that's by-the-by...

Do a "show run" and copy out whatever appears below "Interface B8".

You should probably re-enable flow-control, I can see that's off.

You have a bunch of 1Gb interfaces so devices communicating across sites are going to be sending data faster than the inter-site link can handle.

[M.Breitenbach]

hello,

interface B8
   name "LAN LINK"
   speed-duplex 100-full
exit

our provider told us to set flow control off.

Flow control on or off doesnt change the number of discards.

its the same on both ports (the old and the new) with or without flow control.

[Richard Brodie_1]

If the link is a bottleneck, then some discards are to be expected. If that's not likely to change, then it might be worth doing some monitoring on the link. I would do some polling of the counters (with Cacti or whatever) and possibly Sflow sampling of the traffic also.

I would prefer a top-down approach when looking at discards. How does the percentage load on the link vary with time? Is my traffic mostly TCP or UDP? Would using different priorities/QoS help?