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On Wednesday, July 20, 2016 06:13:36 PM Jarry wrote: |
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> Hi Gentoo-users, |
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> |
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> I'm going to build a small server with Xen-hypervisor with |
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> Gentoo as dom0 (if it is possible). Comming from ESXi-world, |
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> there is no choice (only true hw-raid is supported). |
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> |
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> But what about Linux? What's preffered way to go? Software-raid |
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> (mdadm), or true hardware raid-controller? I have a few spares |
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> (LSI-9271), these worked quite well with ESXi but I'm not sure |
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> they are supported by Linux at all, and if there is actually |
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> some way of monitoring controller-health... |
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|
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LSI is generally quite well supported with Linux. |
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See: https://www.thomas-krenn.com/en/wiki/Smartmontools_with_MegaRAID_Controller |
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|
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This indicates that LSI cards also provide SMART-data of the disks itself via |
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smartmontools. |
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|
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> Concerning sw-raid, I have used it for quite some time, but |
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> never with Xen (is it actually possible?). |
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Yes, it is possible. But the reason why software raid can be faster on bare |
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metal, might no longer be true when using Xen best practices. |
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Dedicating a limited amount of cores to the dom0 also means that you have less |
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cores available for the software raid part. |
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|
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> Moreover, grub-config |
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> for Xen itself is somehow more complicated and sw-raid could add |
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> extra complexity... |
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|
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Using Grub1: |
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--- |
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title Xen |
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root (hd0,1) |
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kernel /xen.gz dom0_mem=4GB,max:4G console=vga dom0_max_vcpus=1 dom0_vcpus_pin |
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module /kernel-4.1.7-hardened-r1-host softlevel=xen |
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--- |
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|
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I compile in the initramfs and commandline these days. |
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But if using a seperate one, simply add an extra "module" line: |
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|
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--- |
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title Xen |
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root (hd0,1) |
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kernel /xen.gz dom0_mem=4GB,max:4G console=vga dom0_max_vcpus=1 dom0_vcpus_pin |
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module /kernel-3.16.5-gentoo dolvm root=/dev/vg/root rootfstype=ext4 |
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module /initramfs-genkernel-x86_64-3.16.5-gentoo |
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--- |
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|
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> So the question is simple. For Xen-server with Gentoo as dom0, |
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> what do you recommend: sofware- or hardware-raid? |
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> |
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> Any other general tips concerning Xen (particularly with Gentoo |
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> as dom0)? |
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No specific Gentoo-tips, it's actually quite well supported. |
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If you prefer an appliance-like dom0, you could also look into XenServer. |
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There is a free-to-use version available. Downside: the graphical management |
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client is MS Windows only. |
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|
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-- |
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Joost |
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