Diskless i. SCSI boot with PXE HOWTO « \1. Here we will boot a machine (diskless or not, but even if it has a disk it won't be used) entirely from the network using PXE and the i. SCSI protocol. There are a few options to boot a system whose root partition is on i. SCSI: The machine could have a local bootloader that loads a local kernel and initrd.

With suitable options, the initrd scripts are directed to log into an i. SCSI LUN and use it as /. In this case, the LUN that is used as root filesystem does not need to have a kernel or bootloader installed. Same as above, but the kernel and initrd are downloaded using PXE (via TFTP or HTTP). Microsoft Store Saint Louis Movie more. The most interesting option (and the one that will be described here) is booting directly the i. SCSI LUN via PXE.

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In this case, the LUN looks exactly like a local disk, with partitions, MBR, bootloader (grub) etc. The MBR is read and executed, which loads the second- stage bootloader and so on, just as if the disk were local. A peculiar thing about i. SCSI is that it doesn't really like the network going away while a session is connected.

I'm trying to PXE-boot a Cisco UCS C240 server to install a new OS over the network, but it isn't picking up an IP address via DHCP during boot. I get the "No DHCP or. VMware vSphere 6 - Install ESXi 6 to USB to create bootable USB flash key or install ESXi 6 to USB and do a config with VMware Workstation. PXE/BINL - AN01: Windows Network Install. Starting an automated network install of anything from Windows 2000 to Windows 10 taking no more than 15 minutes and a ~3 MB. The NUC itself is not supported by VMware and not listed in the HCL. However, some essential components are listed. ESXi runs out of the box starting with the.

For this reason it is very important that the network be stable and reliable, but there are also a few specific boot- time tweaks to do in the Linux distribution that is being run from i. SCSI. One of them is, of course, supplying the needed i. SCSI information to the kernel; another one is preventing the initscripts from trying to (re)configure the network on the interface that is being used for the i. SCSI session, as this may cause it to go down temporarily. In this case, the network is configured early, by the initrd, and should not be touched afterwards. For this example, we will boot a Debian Wheezy over i.

SCSI, using PXE to read the LUN right from the very beginning (MBR and bootloader stage). For this to work, a PXE implementation that supports booting from i. SCSI is obviously needed.

The second (described here) is to use debootsrap on an existing helper machine to partition, install and prepare the LUN. The specific tweaks described starting from . So from a (possibly Debian or Ubuntu) machine with open- iscsi installed, we can log into it: helper# iscsiadm - m discovery - t sendtargets - p 1.

T 'iqn. 2. 00. 7- 0. Logging in to . For simplicity, here we'll create a 5.

MB swap partition and a 9. G root partition. On BIOS systems, which are still the majority, GPT also needs a small partition at the beginning of the disk, the so- called . See here, here and here for more info (all three documents are very interesting reads). So here's the disk layout: helper# gdisk - l /dev/sda. GPT fdisk (gdisk) version 0.

Partition table scan. MBR: protective. BSD: not present. APM: not present. Found valid GPT with protective MBR; using GPT. In this case, the best option is working with UUIDS, so let's find them: client# blkid /dev/sda.

UUID=. Basically, we need a special initrd that configures the network, logs into the i. SCSI target LUN, mounts it as / and calls pivot. We will provide the needed information in the form of kernel command line arguments. The open- iscsi package includes the necessary initrd hooks to do the above, so let's install it: client# apt- get install open- iscsi. The relevant bit are in /usr/share/initramfs- tools/scripts/local- top/iscsi, where we learn that we can pass information by setting various ISCSI. We also want early (ie, kernel- level) IP configuration, which again can be done with special arguments to the kernel.

We pass all this information by modifying the grub kernel command line, so we need the following line in the client's /etc/default/grub: GRUB. Also, the GRUB. It can be readded back later if wanted. Also note that if the SAN needs authentication more variables are needed, most likely ISCSI.

This is achieved in a simple way by either removing any reference to eth. Debian that the configuration is .

Using i. PXE, all that we have to do is sending this i. PXE script to the client: #!

This is the bare minimum; if your SAN needs authentication, then username and password should also be set before attempting to boot (see the i. PXE docs, and SAN URIs explained).

Test it! So if we boot our client, we should see that i. PXE logs into the LUN and loads GRUB. Opts: (null). .. Opts: (null). Opts: errors=remount- ro.

It is also possible to set the various variables directly in the /etc/iscsi/iscsi. If manual configuration is necessary, there are two ways to include i. SCSI bootoptions in your initramfs: 1) Touch /etc/iscsi/iscsi. This provides flexibility, but if passwords are used, is not very secure.

Available boot line options: iscsi. On the other hand, connecting to single- IP targets like i. SCSI Enterprise Target works fine.