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maiconlp
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Disk I/O

Hello, I've just take over a VMware VSphere environment that there are some points I would like share them here.

sometimes a BD Oracle become slow. this BD is installed on an VM Windows 2008 R2. I've looked in performance disk and sometimes the time of that disk arrives in 500 ms I think it's a longer time.

so... I'm afraid that structure of connections beetwen VMware Hosts ( there are two in cluster ) and storage doesn't be way recommend.

there is only an connection ISCSI SAN between each VMware host and storage. each host has 12 VMs.

What do you think about only one connection with storage ? it's few ? if I put more one connection for each host VMware maybe I'll sense more speed !??!

thanks

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marcelo_soares
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You will need to find out where the latency resides. Where are you seeing the 500ms latency?

Also, check for SCSI communication errors on the vmkernel logs, sometimes the problem resides on a bad cable/switch port.

Marcelo Soares

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rsicilia
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One connection 1 Gbps is not sufficient. In many case the entry level solution propose two Gbps commections for each host.

--

Rocco Sicilia

http://www.roccosicilia.it

Rocco Sicilia [aka: BrC] - http://www.roccosicilia.it - VTSP 4-5, VCP 4-5, vExpert 2013/2014
marcelo_soares
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You will need to find out where the latency resides. Where are you seeing the 500ms latency?

Also, check for SCSI communication errors on the vmkernel logs, sometimes the problem resides on a bad cable/switch port.

Marcelo Soares
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maiconlp
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Hi, thanks.

You will need to find out where the latency resides. Where are you seeing the 500ms latency?

     A: sorry, it was 150ms. I saw in vmware performance manager for that machine. in my guest S.O ( Win2k8 r2 ) shows some high I/O too

Also, check for SCSI communication errors on the vmkernel logs, sometimes the problem resides on a bad cable/switch port.

where is vmkernel logs ? I can't find it in the Vcenter manager. there isn't any alarm about that issue in vcenter manager.

thanks

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zXi_Gamer
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where is vmkernel logs ? I can't find it in the Vcenter manager. there isn't any alarm about that issue in vcenter manager.

thanks

In Esx, the vmkernel log will reside in /var/log/vmkernel

In ESXi, the vmkernel log will be merged in to /var/log/messages and also you can see vmkernel only logs by pressing Alt+f12 in the idle screen of the ESXi server