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Dell PowerEdge R720 Guide
How do I install an operating system?
Due to the customized nature of the Dell server, we do not offer to pre-install any operating systems, because we do not know what kind of RAID and hard drive configuration the client wants. This is why Dell servers are delivered with the Rescue System.
Once the server is online, you need to configure the RAID controller. After that, you can install one of the supported operating systems, either automatically via Robot or manually via the installimage. Alternatively, you could also mount your own ISO image and install an operating system using the KVM function.
Which Operating Systems are supported?
- CentOS 6.4
- Debian GNU/Linux 7
- Ubuntu 12.04 LTS/13.04
- OpenSuSE 12.3
- Fedora 19 (only via VNC)
- Windows Server 2012
installimage -z OMSA
You can also install OMSA at any time in the future using the package manager of your system.
Due to a bug in Fedora 18, it is neccessary to add the kernel option usbcore.autosuspend=-1 to fix the usage of the keyboard in the iDRAC remote console. (see RH#850785)
Unsupported Operating Systems
- Debian GNU/Linux 6.0.7 - Due to a bug in the Intel NIC drivers, the MAC addresses are not properly detected and configured. Using an alternate kernel (eg. from backports) or updating the kernel (to update the driver), should make it possible to run, but this is not guaranteed or supported.
- Windows Server 2008 R2 - Due to the memory limit of 32 GB RAM of the Standard edition and the Web edition, this operating system is not available.
- VMware vSphere/ESXi - Installing this operating system is possible, but the free license is limited to a maximum of 32 GB RAM.
- vSphere/ESXi 5.1 and later can be installed directly without any customizations.
What is the iDRAC?
The iDRAC (integrated Dell Remote Access Controller) is an integrated tool which can perform a multitude of configuration and maintenance tasks. By logging on to the iDRAC, you can fix many problems yourself immediately, instead of having to rely on our support staff.
How do I connect to the iDRAC?
In the order completion mail, there are two IP addresses; one of them for the server itself and the other one for the iDRAC. The login details for the iDARC are noted in the email below the login details for the server itself (they are separate logins).
Just enter the iDRAC IP into the address bar of your browser and confirm any possible security warnings. After that, you will see a web interface and you can log on with the iDRAC login information. At this point, you can use the KVM function, turn the server on and off, mount an ISO image for an installation, and diagnose hardware problems.
How do I change the iDRAC password?
First, log on to the iDRAC and in the menu on the left, select "User Authentication" under "iDRAC Settings". Then, click on the user id of the user whose password you would like to change (for example root, ID 2).
On the new page, select "Configure User" and click on "Next".
On the page that you see now, check the box that says "Change Password", enter the password in both text boxes below, and click on "Apply" on the bottom right of the page.
How do I see the drives?
When you receive your Dell server, it usually does not yet have a RAID configured. This is why you cannot see any logical drives, but only unconfigured drives. So don't worry, your drives are there. However, before you can install an operating system, you need to set up at least one logical drive by configuring the RAID controller.
How do I configure the RAID controller?
There are a wide variety of options available to you for configuring the RAID controller. For instance, you can use the KVM function of the iDRAC to restart the server and press Ctrl-R when you see the message to do so to go to the traditional RAID controller BIOS. Alternatively, you can also get to the RAID settings via UEFI by selecting "Device Settings".
Furthermore, in the Rescue System, you can use the command line tool megacli. Here is a simple example for a first configuration:
- First, you need to decide on the drive configuration you would like to use. The controller offers a multitude of different RAID levels and depending on the number of drives in your server, different RAID configurations are possible. In all further steps, we will assume you chose a RAID 1 configuration with two drives. Please adjust the examples to your needs. The text boxes in each step contain the commands you need to enter in the Rescue System.
- Next, you need to acquire some information about your drives:
megacli -PDList -aAll | egrep "Enclosure Device ID:|Slot Number:|Inquiry Data:|Error Count:|state"
- You will get output similar to this:
Enclosure Device ID: 32 Slot Number: 0 Media Error Count: 0 Other Error Count: 0 Firmware state: Online, Spun Up Inquiry Data: ZX512545333TSQ50NS RAAA
Enclosure Device ID: 32 Slot Number: 1 Media Error Count: 0 Other Error Count: 0 Firmware state: Online, Spun Up Inquiry Data: ZX512545001TSQ50NS RAA0
- Please write down the Enclosure Device ID and the Slot Number of the drives you want to use in this RAID configuration.
- After that, you can create the RAID array:
megacli -CfgLdAdd -r1 [32:0,32:1] WB RA Direct CachedBadBBU -a0
- In that command, you can choose the RAID level by changing the number aftter the option "-r", so for instance "-r1" for RAID 1 or "-r5" for RAID 5. In brackets, you list the drives that you want to use in the RAID array. The entries are separated by commas and always use the pattern Enclosure Device ID:Slot Number. In the above example, the RAID will contain the drives with Enclosure Device ID 32 and Slot Number 1 and 2. Please adjust this command according to the output of megacli on your system.
- At this point, you can use the logical drives normally and partition them or install an operating system directly.
You can find more detailed examples for experts at LSI RAID Controller.
Can I use the drives without configuring RAID?
In order to use the drives directly, as a so-called JBOD (just a bunch of Drives) instead of a RAID, you need to use a walkaround because the built-in controller does not support JBOD directly. You can circumvent this limitation by configuring each drive as an individual RAID 0. That way, you essentially have a JBOD configuration. Please enter the following command in the Rescue System to achieve that configuration.
megacli -CfgEachDskRaid0 WB RA Direct CachedBadBBU -a0
What is the KVM function and how do I use it?
The KVM function, more specifically the KVM over IP function, enables you to use the server over a network just as if you were directly in front of the machine with a screen, a keyboard, and a mouse directly attached. When you log on to the iDRAC, you see a preview of the current video output of the server on the right third of the website.
By clicking on "Launch" next to the preview and confirming all requests, you will initiate a live connection that will enable you to use the server just as any other computer. For some special key combinations (for example Ctrl-Alt-Delete), you need to use the menu entry "Macros" of the KVM window.
How do I turn my server on/off and how do I restart it?
How do I mount an ISO image?
Simply use the option "Virtual Media" in the KVM window and then "Launch Virtual Media". After confirming all requests, you will see another window, in which you can select and mount local drives. There, you can also click on "Add Image" and select an ISO image. After that, check the box "Mapped" left of the newly added ISO image entry in order to make the image available to the server as a drive.
If you restart the server now, you can boot from the image just as you could from any other drive. To do so, please press F11 to go to a boot menu when you see the message to press F11. An even easier way to boot from the image is to select the entry "Virtual CD/DVD/ISO" in the menu "Next Boot" of the KVM window.
How do I diagnose hardware problems?
Under Overview in the iDRAC, you will find a general summary of the condition of certain groups of server components under the heading Server Health. If there is a green check mark next to the group, everything is ok. If you would like to see details about a group of components or about an error that is displayed, just click on the group (for instance Fans). If you see an error, you can either check the technical manual whether or not it is a serious problem, or you include the error message when contacting the Hetzner support staff via Robot.
What is the Dell Open Manage System Administrator Suite (OMSA)?
OMSA enables you to perform certain hardware configuration tasks and to monitor the hardware directly through the operating system. You can find more information about OMSA at the Dell website.
How do I use hardware monitoring?
The iDRAC provides operating system independent comprehensive monitoring of all system components.
In order to use the notification capabilities, a DNS name and a DNS domain need to be configured in the network settings of the iDRAC. To configure this, enter the webinterface and go to iDRAC Settings and then Network. Here, you can enter a domain that you managed under the static DNS domain name. For example:
- DNS DRAC Name: idrac-hetzner-r720
- Static DNS Domain name: example.com
The system will now send emails with the sender address <firstname.lastname@example.org>.
Now, you can both add destination email addresses and configure an SMTP server, all via the menu Alerts -> SNMP and E-mail Settings.
Here, you can enter email addresses to be notified of system events in the E-mail Alert 1 to E-mail Alert 4 fields.
Under SMTP (E-Mail) Server Address Settings, you need to configure the appropriate SMTP server.
Finally, by clicking on the button send, you can send a test email to the addresses you entered. If the email is temporarily not delivered (eg. due to greylisting) you will receive an error message. In this case, the email will be cached for later delivery.
How do I secure the iDRAC?
To secure the iDRAC against unauthorized access beyond just changing the password, you can configure IP filtering and blocking. It is possible to restrict access to either a single IP address or a range of IP addresses.
To configure this, enter the web interface and go to iDRAC Settings and then Network. Click on the link Advanced Settings. Here, you can enter an IP address and a subnet mask from which access is allowed. To limit access to a single IP address, enter 255.255.255.254 as the subnet mask (255.255.255.255 is not supported by the iDRAC). To allow access from a range of IP addresses, a subnet mask must be entered which, when combined with the IP address, contains all IP addresses from which access should be permitted.
SSH connections to the iDRAC are disabled on all Hetzner systems by default. Depending on your needs, you can activate ssh connections as well.
What kinds of memory configurations are available?
The Dell PowerEdge R720 offers several configuration options for the system memory to suit for different applications and requirements. In the optimized default configuration, the full capacity and performance are offered. The ECC standard allows for single-bit errors to be corrected and multi-bit errors to be detected. For even greater demands beyond that, the following configurations are possible:
- Mirroring - The memory content is kept redundantly. For maximum security, only half the storage capacity is available.
- Advanced ECC - Additional error correction through more elaborate checks during memory access. The storage capacity is reduced by 33%. High performance, but less than with the optimized configuration.
- Sparing - One bank is used as a spare. If one memory bank fails, the systems switches to the spare on the fly. The storage capacity is reduced by 33% to 50%.
Which hardware configurations are available?
You can find our current Dell offers on our website.
Which RAID controller does the server use?
The integrated PERC H710 is a powerful enterprise class RAID controller. 512 MB of non-volatile (flash backed) cache provide enhanced reliability and stability. Based on the LSI SAS 2208 dual core ROC (RAID On Chip), the PERC H710 controller delivers high performance and simplified management.
Where do I find additional information?
Dell offers an [[Ftp: as well as a technical manual.