Bij een van onze klanten moest een Sun Storage systeem gekoppeld worden aan een stack van Cisco 3750 switches. Deze switches gebruiken wij vaak als netwerk componenten voor storage en server systemen omdat ze redelijk goedkoop zijn, makkelijk redundantie bieden door middel van het stacken van de switches en goede performance bieden.
Redundantie implementeren we door middel van LACP (802.3ad) op de switches, LACP mag cross-stack aangemaakt worden, dit in tegenstelling tot Cisco’s eigen PAgP waar alle portmembers in een etherchannel op 1 stackmember aanwezig moeten zijn. De configuratie ziet er dan als volgt uit:
interface GigabitEthernet1/0/24
description sun-storage
channel-protocol lacp
channel-group 15 mode active
interface GigabitEthernet2/0/24
description sun-storage
channel-protocol lacp
channel-group 15 mode active
interface Port-channel15
description sun-storage
switchport access vlan 20
switchport mode access
Op de Sun Storage zet je de volgende parameters onder datalink:
Policy: L2
Mode: Active
Timer: Long
Om te controleren of de port-channel goed werkt kun je een show int port-channel 15 uitvoeren, dit geeft de volgende output:
aazoo-testswitch3750#show int port-channel 15
Port-channel15 is up, line protocol is up (connected)
Hardware is EtherChannel, address is 0026.986d.a287 (bia 0026.986d.a287)
Description: sun-storage
MTU 1500 bytes, BW 2000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, link type is auto, media type is unknown
input flow-control is off, output flow-control is unsupported
Members in this channel: Gi1/0/24 Gi2/0/24
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/0 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 1000 bits/sec, 1 packets/sec
92 packets input, 10638 bytes, 0 no buffer
Received 92 broadcasts (66 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 66 multicast, 0 pause input
0 input packets with dribble condition detected
708 packets output, 70378 bytes, 0 underruns
0 output errors, 0 collisions, 7 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
Om een overzicht van de port-channel te kunnen krijgen gebruik je show etherchannel, dit geeft een overzicht zoals:
aazoo-testswitch3750#show etherchannel
Channel-group listing:
----------------------
Group: 15
----------
Group state = L2
Ports: 2 Maxports = 16
Port-channels: 1 Max Port-channels = 16
Protocol: LACP
Minimum Links: 0
aazoo-testswitch3750#sh etherchannel 15 summary
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use f - failed to allocate aggregator
M - not in use, minimum links not met
u - unsuitable for bundling
w - waiting to be aggregated
d - default port
Number of channel-groups in use: 7
Number of aggregators: 7
Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
15 Po15(SU) LACP Gi1/0/24(P) Gi2/0/24(P)
Voor uitgebreide informatie voer je het commando show ether-channel detail uit:
aazoo-testswitch3750#sh etherchannel 15 detail
Group state = L2
Ports: 2 Maxports = 16
Port-channels: 1 Max Port-channels = 16
Protocol: LACP
Minimum Links: 0
Ports in the group:
-------------------
Port: Gi1/0/24
------------
Port state = Up Mstr Assoc In-Bndl
Channel group = 15 Mode = Active Gcchange = -
Port-channel = Po15 GC = - Pseudo port-channel = Po15
Port index = 0 Load = 0x00 Protocol = LACP
Flags: S - Device is sending Slow LACPDUs F - Device is sending fast LACPDUs.
A - Device is in active mode. P - Device is in passive mode.
Local information:
LACP port Admin Oper Port Port
Port Flags State Priority Key Key Number State
Gi1/0/24 SA bndl 32768 0xF 0xF 0x108 0x3D
Partner's information:
LACP port Admin Oper Port Port
Port Flags Priority Dev ID Age key Key Number State
Gi1/0/24 SA 4096 0021.2845.bd6c 9s 0x0 0x3E9 0x3 0x3D
Age of the port in the current state: 0d:00h:17m:08s
Port: Gi2/0/24
------------
Port state = Up Mstr Assoc In-Bndl
Channel group = 15 Mode = Active Gcchange = -
Port-channel = Po15 GC = - Pseudo port-channel = Po15
Port index = 0 Load = 0x00 Protocol = LACP
Flags: S - Device is sending Slow LACPDUs F - Device is sending fast LACPDUs.
A - Device is in active mode. P - Device is in passive mode.
Local information:
LACP port Admin Oper Port Port
Port Flags State Priority Key Key Number State
Gi2/0/24 SA bndl 32768 0xF 0xF 0x208 0x3D
Partner's information:
LACP port Admin Oper Port Port
Port Flags Priority Dev ID Age key Key Number State
Gi2/0/24 SA 4096 0021.2845.bd6c 10s 0x0 0x3E9 0x4 0x3D
Age of the port in the current state: 0d:00h:17m:06s
Port-channels in the group:
---------------------------
Port-channel: Po15 (Primary Aggregator)
------------
Age of the Port-channel = 3d:23h:10m:39s
Logical slot/port = 10/15 Number of ports = 2
HotStandBy port = null
Port state = Port-channel Ag-Inuse
Protocol = LACP
Port security = Disabled
Ports in the Port-channel:
Index Load Port EC state No of bits
------+------+------+------------------+-----------
0 00 Gi1/0/24 Active 0
0 00 Gi2/0/24 Active 0
Time since last port bundled: 0d:00h:17m:06s Gi2/0/24
Time since last port Un-bundled: 0d:00h:17m:13s Gi2/0/24
