Hi, In last summer, I have had same problems with Dell + CentOS + multipath combination. For example I/O errors and stability problems on the initiator machines. The initator machines are (in a Pacemaker cluster): - Dell R310 - Broadcom 5709 Gigabit Ethernet card (4-port) - CentOS 5.4 - 2 Ethernet ports on initiator machines, 2 Ethernet ports in target machines --> 4 iSCSI pathes by initiators
Irrespectively of iSCSI, we met the Broadcom MSI-X interrupt problem (corrected in RHEL/CentOS 5.5). We met more (iSCSI) problems with Broadcom cards, which are described on a Dell support page: http://support.dell.com/support/edocs/software/rhel_mn/rhel5_4/en/index.htm
Since the CentOS is a recompiled RedHat, all RHEL problems and solutions are true for CentOS ;-) The Broadcom driver source code is frequently changed. RedHat follows the Broadcom kernel drivers and iscsi-initiator-utils with some months latency. CentOS follows the RedHat with some days/weeks/monts.
Maybe you can find a solution for your problem on a newer Dell support page: http://support.dell.com/support/edocs/software/rhel_mn/rhel5_5/en/index.htm Or here: http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/DM_Multipa... http://opensource.marshall.edu/papers/rhel5-iscsi-HOWTO.pdf
Some tips: - I've read somewhere about iSCSI multipath I/O errors, which can be a normal behaving in a multipath environment at boot time. (?) - Persistent reservation might be usefult against iSCSI multipath I/O errors. - Disabling iSCSI offload feature (for example: iSCSI over Broadcom ) and TCP offload feature (for example: NFS over Intel) may be helps. - The iSCSI kernel drivers and iscs-initiator-utils must be updated together.
Finally, some comments: - Never use Broadcom GbE card. Intel might be better (mostly) - The Dell is hardware manufacturer (supplier), not an OS/driver/utility developer. If you would like to get more support, you may buy RHEL licenses (with the Dell hardware or from RedHat). Sometime it's cheaper than taking days for a problem (but sometime not). - IBM compiles the latest Broadcom driver if required, see: http://www-947.ibm.com/support/entry/portal/docdisplay?lndocid=MIGR-5073130 - Some Dell hardwares have only x86_64 RedHat certifications See: https://hardware.redhat.com/show.cgi?id=632145 (R310 + RHEL 6)
BR,
Peter
On Sat, Jan 22, 2011 at 18:36, Rajagopal Swaminathan raju.rajsand@gmail.com wrote:
Greetings,
On 1/22/11, Edward Morbius dredmorbius@gmail.com wrote:
CentOS is not a Dell-supported configuration, and we've had little helpful advice from Dell. There's been some amount of FUD in that Dell don't seem to know what Dell's own software installation (the md3
Dell doesn't seem to have much OS experience generally.
+1
It is to be expected from Dell as they outsource support to non-"equal opportunity" employers who do not hire support agents beond 40 years of age (per HR).
Above fact. below imho
Now, experience often helps reach the source of the problem much faster that fast-talking street-smart agents who proliferated.
It is sad that IT industry treats its early community members so callously.
I don't know but Dell seems to be headed the Sun way -- open for takeover by HP/IBM
Above imho.
Regards,
Rajagopal _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos