Supported FC Switches for CA

[Hauser Juergen]

Hello,we are using 2 EVA's 4400 and CA. We have the following FC Switches in our configuration: HP StorageWorks 8/20q.
We now have a very poor performance on servers using CA. So we changed to asynchronous and also to logging. So for me this is not normal and I opened a case at HP. But after one week analysing they told me that the Switches are not supported for CA. So I told this my supplier and he told me that this not true, but I didn't get an official document proofing the support of the Switches. This is now going for over 10 weeks.
So do someone know if the Switches are supported? And when they are supported, why is the performance so poor in our config?

Best regards,
Juergen

[chris barnett_2]

Hi Juergen. Qlogic switches are not supported by HP in a CA enviroment. see this docs.

http://h20272.www2.hp.com/utility/document.aspx?docurl=Shared%20Documents/an/continuous_access/CA_EVA_IG_2009_08_04.pdf

and

http://h20272.www2.hp.com/utility/document.aspx?docurl=Shared%20Documents/hw/iscsi/IP_Distance_Gateway_mpx110_Stream_2009_08_07.pdf

Only m, b and c series switches are supported. Without further information on the connectivity between the EVA's it's difficult to be sure what is the problem. Apart from the obvious one with the switches. but I would look at the latency of the link. Must be less than 100ms round trip time. the link jitter. less than 10ms in 24 hours, and the available bandwidth. If for example you have a 100Mb comms line and you are using FCIP then you will limit the source array Vdisks that are in a DR groups to about 10MB/sec write rate in synchronous mode

[chris barnett_2]

Forgot to include the SAN design Guide. See section IV

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c00403562/c00403562.pdf

[Hauser Juergen]

Hi Chris,

how could I check the latency, jitter and the bandwidth?

[chris barnett_2]

Hi Juergen. If this is a IP link. it's going to be difficult if it's in use, so you may have to suspend the DR groups to do any measurments. Latency can be roughly measure with a ping on the link to the other end. so the round trip time will give you the latency. Bandwidth, you will need to call your WAN providor to find out or with CA running you could create a dummy Vdisk, populate it with data and create a new DR group. Time how long it takes to do a full copy, you can then roughly workout what the link speed is. this is all assuming you are using an IP link with somthing like MPX110 IP distance gateways.

[Hauser Juergen]

Hi Chris,
thanks for the fast response.
But it seems to be a little misunderstanding. Both of our EVA's is in the same building. The distance is about 50m. They are connected through a FC connection.