Hello, 

we tested clustering with ZFS and the setup looks like this: 

- 2 head nodes (nodea, nodeb)
- head nodes contain l2arc devices (nodea_l2arc, nodeb_l2arc)
- two external jbods
- two mirror zpools (pool1,pool2)
   - each mirror is a mirror of one disk from each jbod
- no ZIL (anyone knows a well priced SAS SSD ?)

We want active/active and added the l2arc to the pools. 

- pool1 has nodea_l2arc as cache
- pool2 has nodeb_l2arc as cache

Everything is great so far. 

One thing to node is that the nodea_l2arc and nodea_l2arc are named equally ! 
(c0t2d0 on both nodes).

What we found is that during tests, the pool just picked up the device 
nodeb_l2arc automatically, altought is was never explicitly added to the pool 
pool1.

We had a setup stage when pool1 was configured on nodea with nodea_l2arc and 
pool2 was configured on nodeb without a l2arc. Then we did a failover. Then 
pool1 pickup up the (until then) unconfigured nodeb_l2arc. 

Is this intended ? Why is a L2ARC device automatically picked up if the device 
name is the same ? 

In a later stage we had both pools configured with the corresponding l2arc 
device. (po...@nodea with nodea_l2arc and po...@nodeb with nodeb_l2arc). Then 
we also did a failover. The l2arc device of the pool failing over was marked as 
"too many corruptions" instead of "missing". 

So from this tests it looks like ZFS just picks up the device with the same 
name and replaces the l2arc without looking at the device signatures to only 
consider devices beeing part of a pool.

We have not tested with a data disk as "c0t2d0" but if the same behaviour 
occurs - god save us all.

Can someone clarify the logic behind this ? 

Can also someone give a hint how to rename SAS disk devices in opensolaris ? 
(to workaround I would like to rename c0t2d0 on nodea (nodea_l2arc) to c0t24d0 
and c0t2d0 on nodeb (nodea_l2arc) to c0t48d0). 

P.s. Release is build 104 (NexentaCore 2). 

Thanks!
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