4 4 3:VMware Requirements & Restrictions

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Copyright © SEP AG 1999-2019. All rights reserved.

Any form of reproduction of the contents or parts of this manual is allowed only with the express written permission from SEP AG. When compiling and designing user documentation SEP AG uses great diligence and attempts to deliver accurate and correct information. However, SEP AG cannot issue a guarantee for the contents of this manual.

Docs latest icon.png Welcome to the latest SEP sesam documentation version 4.4.3/4.4.3 Grolar. For previous documentation version(s), check VMware archive.


Overview

Quick Start 3.png
Quick setup
  1. Read and think about the relevant transport mode first. Depending on your environment, proceed as follows:
    1. Backup VMs over LAN (NBD) – no special configuration is required.
      • Add your ESX Server (single server environment) or vCenter Server (clustered environment) as a SEP sesam client.
      • Select the access mode: PROXY (it enables you to perform a backup without installing the SEP sesam software on the ESX and vCenter Server).
      • Under the tab vCenter Access or ESX Server Access, respectively, select a data mover; in this example, this is your backup server.
      • Performance: Normal/slow.
    2. Backup VMs over LAN via a proxy VM: Install a small new VM (Windows or Linux) in your environment.
      • Requirements: 2 cores, 8 GB RAM, 50 GB disk.
  2. Configure the VM backup.


This article describes configuration requirements and restrictions of SEP sesam integration with VMware. Note that the procedures introduced in this article are only the required pre-configuration steps. For details on VMware integration key features and backup configuration, see VMware Backup.

VDDK

SEP sesam requires the VMware Virtual Disk Development Kit (VDDK) to be installed on SEP sesam data mover (SDM-VV). The VDDK installation procedure differs depending on your SEP sesam version and operating system:

  • On Windows, VDDK is installed automatically during the SEP sesam installation. Depending on SEP sesam version, either VDDK 6.0.2 or VDDK 6.0.3 is installed (for details, see VMware support matrix). However, with new vSphere 6.5 neither of VDDK 6.0.x versions provides SAN transport support when using datastores formatted with new VMFS 6.0 filesystem. If you intend to back up VMs residing on VMFS 6.0 datastores using SAN transport mode, you have to install VDDK 6.5 or later manually. For details, see Installing VDDK.
  • On Linux, you have to install the required VDDK version manually. For details on the required version, see VDDK Compatibility Matrix. For details on installation, see Installing VDDK.
  • If a VDDK is already installed on the data mover to which you intend to install SEP sesam or going to upgrade to the newest SEP sesam version, the existing VDDK version is uninstalled and a new version of VDDK is unpacked.

SEP sesam data mover for VMware vSphere (SDM-VV)

A data mover for VMware vSphere is required to run a SEP sesam backup and restore in a vSphere environment with vStorage API. SEP sesam data mover is a functional role allowing access to a third-party software API. It tells the SEP sesam Server that the original client can only be reached by sending the request to the data mover. A data mover role for VMware vSphere can be combined either with a SEP sesam Server, SEP sesam Remote Device Server or a SEP sesam Client. Any of these can serve as a SEP sesam data mover to transfer (send or receive) data between SEP sesam Server and VMware vSphere Farm. Note that your data mover has to match the version of your SEP sesam Server. This means that you have to update the data mover to the same version as your SEP sesam Server each time you update the server.

Data mover system requirements

Supported operating systems:

  • First, check the VDDK Compatibility Matrix and select the VDDK version suitable for your environment. Before you deploy a SEP sesam data mover, determine the matching VDDK version and the supported data mover operating system. As a rule of thumb, Windows v. ≥ Windows 2016/WIN 10 (64-bit) and Linux v. ≥ SLES 12/RHEL 7 can be used as a data mover in most cases. For information which operating systems are supported by the VMware for the specific VDDK, check the respective VMware VDDK release notes. Note that the VMware policy concerning backward and forward compatibility is for VDDK to support N-2 and N+1 releases (the two previous major versions and the next minor version).
  • Information sign.png Note
    • Even though installing the SEP sesam data mover on unsupported operating system might work, SEP sesam cannot provide any support for such configuration.
    • When upgrading a data mover to a newer version, always check that the operationg system is supported as VMware might have dropped support from one VDDK release to the next release.
  • Fast network interface (1 Gbit max. = 390 GB/h; 10 GBit max. = ~ 2,x TB/h)
  • CPU = Min. 4 cores
  • RAM = Min. 8 GB
  • Any of the following SEP sesam components must be installed: SEP sesam Server, RDS or client.
  • A regular path backup has to work.
  • VMware VDDK must be installed on the data mover; VDDK is installed automatically during the SEP sesam installation on Windows. On Linux, you have to install the required VDDK version manually. For details, see Installing VDDK on Linux.

Configure VMware datamover.jpg

Selecting the best VMware transport mode for your environment

VMware supports the following access methods or transport modes to transport backup data: NBD (network block device) over LAN, NBD with encryption (NBDSSL), SAN, and SCSI HotAdd. For detailed information, see VMware article Virtual Disk Transport Methods.

Select the desired transport mode for backups of your VM according to your network requirements. The SAN and HOTADD allow for faster LAN-free backups. The other two are over-the-network backup and restore using NBD (network block device) or NBDSSL (secure NBD).

For example, NBD transport mode requires LAN between the data mover and SEP sesam. HotAdd requires the data mover to be a virtual machine (VM) running in the same data center as a VM which is to be backed up. SAN requires that the data mover (Windows) is read-only connected to the storage where the VMs are running. For details on each transport mode and their requirements, see VMware article Tips and best practices for transport modes.

The following table can help you define the optimal transport mode in relation to the backup environment and desired operation.

Transport mode Backup environment Performance Pitfalls
SAN Supported only on a physical machine – VMware backup host (data mover) must be a physical SEP Sesam Server or RDS with access to Fibre Channel or iSCSI SAN containing the virtual disks to be accessed.
Make sure that datastore LUNs are accessible to the VMware data mover.
Additionally, follow the VMware vSphere 6.0 best practices for SAN transport: "For a Windows Server 2008 and later proxy, set SAN policy to onlineALL. Set SAN disk to read-only except for restore. You can use the diskpart utility to clear the read-only flag. SAN policy varies by Windows Server 2008 edition. For Enterprise and Datacenter editions, the default Windows SAN policy is offline, which is unnecessary when vSphere mediates SAN storage."
Information sign.png Note
If you are using VMware vSphere 6.5 with VMFS 6.0 datastores, ensure that you have the VDDK 6.5 or later version installed or your backups will fail. For details, see VDDK Compatibility Matrix.
An efficient method to offload backup traffic from the LAN and move it over a SAN. Often the best performing choice for backups for array-based storage. Not a good choice for restores because it has the worst performance on thin disks.
Note that CBT must be disabled for SAN transport restores. For details, see Changed Block Tracking (CBT).
For restore, SEP sesam recommends that you prepare a separate or existing VM sitting on the ESX environment with a SEP sesam Client. This VM should then be used as a data mover for VM restores.
HotAdd Supported for backup proxy as a virtual machine – the data mover must be a VM running in the same data center as VM which is to be backed up. The backups can be processed over SAN or LAN. The data mover can be a Windows VM with installed SEP sesam Client, or any Linux system supported by VMware that has a required VDDK version installed.
Check VMware article Best Practices for HotAdd Transport for more requirements and limitations.
HotAdd mode can achieve close to SAN-mode performance if SAN is not available.
Note that SCSI HotAdd feature is not enabled for all vSphere editions, therefore customers with, for example, vSphere Essentials or Standard editions are not able to perform HotAdd proxy-based backup.
Take the following into account if using HotAdd with a VM backup host:
  • HotAdd is a SCSI feature and does not work for IDE disks.
  • HotAdd transport does not work with SATA virtual disks for ESXi running version prior to 5.5. From VDDK version 5.5 onwards, SATA disks are supported, however HotAdd advanced transport is not supported for SATA drives. Check VDDK 5.5 Release Notes for further caveats.
  • If the HotAdd proxy VM resides on a VMFS-3 volume, make sure that you select a volume with appropriate block size. For details, see VMFS-3 Block Size for HotAdd Backup Proxy. This caveat only applies to VMFS-3 volumes while VMFS-5 volumes have always 1MB file block size.
NBD (LAN) Network block device (NBD) is a Linux-style kernel module that treats storage on a remote host as a block device. Virtual machines are backed up over an Ethernet LAN. Slow transport mode, but still faster and consuming fewer resources than NBDSSL.
At least 10GigE is required for backup network.
Network connectivity between proxy server and ESXi server with an open TCP port 902 must be ensured.
Not recommended except for restore instead of using SAN restore, the latter being really slow if used for restore of thin provisioned disks.
Ensure that the number of network file copy (NFC) connections to the ESX\ESXi host is not exceeded. For details, see NFC Session Connection Limits.
NBDSSL (encrypted NBD) The same as NBD, except NBDSSL uses SSL to encrypt all data passed over the TCP/IP connection which can decrease performance. The slowest transport mode because LAN operations use secure NBD (NBDSSL) and large virtual disks can take a long time to transmit.
At least 10GigE is required for backup network.
Network connectivity between the proxy server and ESXi server with an open TCP port 902 must be ensured.
It is not recommended to use NBDSSL if over-the-wire encryption is not required.
Ensure that the number of network file copy (NFC) connections to the ESX\ESXi host is not exceeded. For details, see NFC Session Connection Limits.

Best practices: Scalable LAN-free backup over SAN transport

LAN-free backup over SAN transport is the fastest transport method for SEP sesam backup on SAN connected ESXi hosts. The VM backup performance can be scaled up with SEP sesam. This allows for simultaneous backups of a large number of virtual machines.

The following diagram shows the structure and operating principle for scalable LAN-free backup over SAN transport: SEP sesam Best-Practice scalable VMware LAN-free-Backup 02.png

The modular structure of SEP sesam supports the scale-out principle, allowing for multiple identical Remote Device Servers (RDS) to be used.

The following requirements apply to the scalable LAN-free backup over SAN transport scenario:

General requirements for SAN transport

  • The VMware datastore must support hardware acceleration. To check whether hardware acceleration is supported by the specified VMware datastore, open the vSphere Client, choose ESXi host and switch to tab Configuration. Then choose Storage and check the settings.
  • Hardware acceleration must also be enabled on each ESXi host. To enable it, select the Configuration tab and choose Advanced Settings. Select the section DataMover and ensure that both values are set to 1. Then select the section VMFS3 and make sure that VMFS3.HardwareAcceleratedLocking is set to 1.
  • Check VMware article Best practices for SAN transport for other requirements and limitations.
  • If you are using VMware vSphere 6.5 with VMFS 6.0 datastores, ensure that you have the VDDK 6.5 or later version installed or your backups using SAN transport mode will fail. For details, see VDDK Compatibility Matrix.

Additional requirements for SAN transport with Linux proxy

On Linux, a SCSI reservation conflict can occur during SAN access. This causes the backup/restore to fail. To prevent this, proceed as follows.

Start a terminal on each ESXi server and execute the command:

vmkfstools -Ph -v1 /vmfs/volumes/<name of VMware datastore>

For example:

vmkfstools -Ph -v1 /vmfs/volumes/SAN-test-volume/

The output might be similar to the following:

Mode: public
Partitions spanned (on "lvm"):
        naa.600000e00d280000002801dd00050000:1

If a Mode is public, this might lead to SAN errors on Linux. To prevent this, enable ATS (Atomic Test & Set). Make sure that no VM is running on the respective VMware datastore when enabling ATS. Execute the following command on each ESXi server with public mode:

vmkfstools --configATSOnly 1 /vmfs/devices/disks/<naa-id]:[partition-number>

For example:

vmkfstools --configATSOnly 1 /vmfs/devices/disks/naa.600000e00d280000002801dd00050000:1

In our example, the device name naa.600000e00d280000002801dd00050000:1 was shown. Now execute the first command again:

 vmkfstools -Ph -v1 /vmfs/volumes/<name of VMware datastore>

The output should be:

Mode: public ATS-only

The usage of ATS should prevent the SAN errors on Linux proxy to occur.

SEP sesam Backup Server:

  • Hardware minimal requirements: Intel 4 Core Server CPU or AMD Server 6 Core CPU, min. 16GB RAM
  • Backup LAN: 10 Gbit (the VM backup data is transferred through the SAN)
  • SAN connectivity: Not required for the backup server

SEP sesam Remote Device Server:

  • Hardware minimal requirements: Intel 4 Core Server CPU or AMD Server 6 Core CPU, min. 16GB RAM
  • Backup LAN: 10 Gbit (the VM backup data is transferred through the SAN)
  • SAN connectivity: All VMware LUN's must be connected via SAN and be visible. For iSCSI example, see also Linux man page iscsiadm.
  • Backup storage: Connection of the tape hardware and disk backup storage via FC, iSCSI, or SAS.
  • VDDK: On all RDSs the relevant VMware VDDK must be installed. For details on supported versions, see VDDK Compatibility Matrix.
  • vCenter: Can be installed on an RDS as vCenter for Windows, or the VMware vCenter appliance can be used as a VM.
  • Data mover (proxy): The machine serving as a data mover must meet the following system requirements (applicable requirements are without Si3 deduplication).

The following are the hardware requirements for the SEP sesam Server or RDS. They are similar for both, except in that the space for the SEP sesam database required on the file system is not necessary for RDS.

The hardware requirements for the SEP sesam Server or RDS represent the common requirements. Additional amount of RAM/CPU may be required for bigger Si3 data stores. For details, see Si3 Deduplication Hardware Requirements.

Requirements SEP sesam Server Standard edition SEP sesam Advanced Server edition SEP sesam Premium Server edition SEP sesam Enterprise Server
Memory (without Si3 deduplication) 8 GB RAM Minimum 16 GB RAM 32 GB RAM Minimum 64 GB RAM
Memory (with Si3 deduplication) Minimum 16 GB RAM Minimum 32 GB RAM 64 GB RAM Minimum 128 GB RAM
Core (without Si3 deduplication) 1x CPU with 4 cores (≥ 2,4 GHz) 1x CPU with 8 cores (≥ 2,4 GHz) Minimum 1x CPU with 8 cores (≥ 2,4 GHz) Minimum 2x CPUs with 4 cores (≥ 2,4 GHz)
Core (with Si3 deduplication) 1x CPU with 6 cores (≥ 2,6 GHz) 2x CPUs with 8 cores (≥ 2,6 GHz) 2x CPUs with minimum 8 cores (≥ 2,6 GHz) Minimum 2x CPUs with 8 cores (≥ 2,6 GHz)
Minimum hard disk space for SEP sesam metadata 100 GB 300 GB 500 GB 500 GB
No. of backup clients Up to 15 Recommended up to 50 Recommended up to 150 Recommended for more than 150

Restrictions

Independent disks or disks with physical raw device mapping will not be backed up.
For VMs with at least one independent disk or disks with physical raw device mapping we recommend to perform backups in the virtual machine with our SEP sesam Client to have consistent backups.

See external references

Known issues

If you have problems with VMware, check the Troubleshooting Guide.

See also

VMware Backup (latest)VMware Backup 4.4.3Changed Block Tracking (CBT)VMware RestoreVMware Single File RestoreVMware Instant RecoveryVDDK Compatibility MatrixInstalling VDDK

External references