APA on Cisco 3750 switches

[Tim Nelson]

There are a lot of APA posts in the forums but none specific to this.

We have been using APA with CISCO switches for some time now but am configuring some new servers with new 3750 switches. I believe some things have changed. Below is the scenario.

We are attempting to aggregate across switches, which the older switches were not capable of, and ran into some weird issues when using LACP as the protocal.

Manual configuration works fine but during reboot it seems as if LACP takes a little longer to aggregate and consequetially when the "/sbin/init.d/net start" is executed next during reboot the aggregated LANs are not yet ready and IP config fails.

BTW the WAN guys set the ports to passive mode as active kept suspending the ports.

We are working on setting some switch ports back to FEC_AUTO to see if the same delay occurs with that protocal.

Anyone run into this before ?

[Andy Torres]

I'm not sure if this will help or not, but we were able to get APA going on a couple ports of one Catalyst 2950 using LACP_AUTO. Both ports are set in the same VLAN, and the same admin group. Aggregate mode is set to auto on the switch side.

We have not attempted to aggregate across switches but we plan to very soon, hopefully to balance the load and provide higher availability. We're upgrading to Catalyst 4506. I'm interested to see how this thread pans out.

I'm glad you asked the question. I'll set a reply reminder and maybe we can both learn something.

[Tim Nelson]

Thanks Andy.


Seems the LACP_AUTO acts kinda goofy. Some aggregates come ready on reboot, some not, some ports in an aggregate go into default state and must be manually set to MANUAL then back to LACP_AUTO.

Will let you know what comes about.

[Andy Torres]

We've only got two links to the aggregate right now, and net & apa start up pretty close to each other in /sbin/rc3.d:

lrwxr-xr-x 1 bin bin 18 Oct 3 14:14 S337hpapa -> /sbin/init.d/hpapa
lrwxr-xr-x 1 bin bin 17 Sep 20 2004 S337vlan -> /sbin/init.d/vlan
lrwxr-xr-x 1 root root 16 Sep 20 2004 S340net -> /sbin/init.d/net

Are you seeing anything in your logs to detect a failure to link? Our latest /etc/rc.log looks like this:

Configure HP AUTO-PORT AGGREGATION interfaces
Output from "/sbin/rc2.d/S337hpapa start":
----------------------------
DLPI version is 2
/sbin/rc2.d/S337hpapa started.
Please be patient. This may take about 40 seconds.
NOTE: APA has set its internal max linkaggs value to 5.
HP_APA_DEFAULT_PORT_MODE = MANUAL
/usr/sbin/hp_apa_util -S 0 LACP_AUTO
/usr/sbin/lanadmin -X -k 0 900 900
New Administrative Key = 900
/usr/sbin/hp_apa_util -S 1 LACP_AUTO
/usr/sbin/lanadmin -X -k 1 900 900
New Administrative Key = 900
lan900
/usr/sbin/lanadmin -X -l LB_MAC 900
New Load Balancing = 2
/usr/sbin/lanadmin -X -y off 900
New Hot Standby = OFF
/usr/sbin/lanadmin -X -k 900 900 900
New Administrative Key = 900
/sbin/rc2.d/S337hpapa Completed successfully.

Configure VLAN interfaces
Output from "/sbin/rc2.d/S337vlan start":
----------------------------

Configure LAN interfaces
Output from "/sbin/rc2.d/S340net start":
----------------------------

How about yours?

[Tim Nelson]

I have three separate LANs on three separate aggregates.

rc.log looks like below. I even added another 15 second sleep in the hpapa start script on top of the 15 second one that was already there.

Another little tidbit (HP seems to reference FEC and PaGP as the same).
Cisco fast ether channel (FEC) enabled by using "on".
"auto" on the switch enables PAgP ( which cannot do cross switch aggregation ).
"active" enables LACP
In order to use FEC (Fast Ether Channel) then the mode needs to be MANUAL. i.e. not PAgP or LACP.

Also, It still seems like using LACP across switches takes too long to negotiate. I will attempt to toss in another 60 second delay to the startup file

lan900
/usr/sbin/lanadmin -X -l LB_MAC 900
New Load Balancing = 2
/usr/sbin/lanadmin -X -y off 900
New Hot Standby = OFF
/usr/sbin/lanadmin -X -k 900 1 900
New Administrative Key = 1
lan901
/usr/sbin/lanadmin -X -l LB_MAC 901
New Load Balancing = 2
/usr/sbin/lanadmin -X -y off 901
New Hot Standby = OFF
/usr/sbin/lanadmin -X -k 901 2 901
New Administrative Key = 2
lan902
/usr/sbin/lanadmin -X -l LB_MAC 902
New Load Balancing = 2
/usr/sbin/lanadmin -X -y off 902
New Hot Standby = OFF
/usr/sbin/lanadmin -X -k 902 3 902
New Administrative Key = 3
/sbin/rc2.d/S337hpapa Completed successfully.

Configure VLAN interfaces
Output from "/sbin/rc2.d/S337vlan start":
----------------------------

Configure LAN interfaces
Output from "/sbin/rc2.d/S340net start":
----------------------------
ERROR: lan900 interface: ifconfig: no such interface
ERROR: lan901 interface: ifconfig: no such interface
ERROR: Failed to add route entry because its interface is not