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_Multipath 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 at gmail.com> wrote: > > Greetings, > > On 1/22/11, Edward Morbius <dredmorbius at 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 at centos.org > http://lists.centos.org/mailman/listinfo/centos