GFS backup scheme in Symantec Backup Exec

Grandfather-Father-Son is an industry standard backup scheme, where you have 5 daily backups, 5 weekly backups and as many monthly as you need. Symantec Backup Exec has prebuilt policy for GFS, but before going into configuring backup scheme itself, lets talk a little bit about general backup job configuration in Backup Exec.

Basic Terminology

Inside user interface you see Jobs, Policies, Selection Lists and Media Sets. First of all you need to create Selection List, which describes what you want to backup. There you select files and folders from your Windows, Unix or NDMP servers. Then you create Media Set, which is a collection of tapes with particular append and retention periods. Append period specifies how long data can be added to the same tape and retention period tells for how long data cannot be overwritten. Retention period starts form the time of last append to the tape. Then you create Policy. Policy, by means of templates, defines when backup jobs are run, where backups are stored and what is the type of backup – incremental, differential or full. One policy can consist of several templates. In template you specify backup date and time, as well as target tape library.

GFS Implementation

Backup Exec has a template for GFS backup rotation scheme. Click “New policy using wizard”, choose GFS scheme and then select schedule, target backup device and media sets for daily, weekly and monthly backups. By default Backup Exec suggests the following configuration.

Three tape media sets:

• Daily Media Set – 1 week overwrite, 1 week append
• Weekly Media Set – 5 weeks overwrite, 5 weeks append
• Monthly Media Set – 1 year overwrite, 1 year append

Policy with three templates:

• Daily Backup – Monday to Friday, Incremental
• Weekly Backup – every Friday, Full
• Monthly Backup – first Saturday of each month, Full

Also Backup Exec automatically creates rules to resolve conflicts. For example when both Daily and Weekly backups try to run on Friday, jobs do not conflict, because weekly backups always supersede daily. Same for monthly.

I personally prefer another schedule. First of all, if you run your jobs after midnight, you will need to shift your schedules from Mon – Fri to Tue – Sat. Additionally, I run monthly backup on the first Saturday of the month. Backup Exec by default (taking into consideration my one day shift) would suggest first Sunday for the monthly backup. However, it doesn’t make much sense to have weekly on Saturday and then monthly next day on Sunday. You would just consume more space without any benefit. Also, you can schedule monthly on the last Saturday of the month, but if the last day is Thursday, for example, then you will loose four business days from your monthly backup.

After the policy is created, you need to create backup jobs using this policy by clicking on New jobs using policy. All three jobs will be created automatically according to Selection List, as well as Policy Schedule, Target, and Backup Type parameters.

I’d also recommend everyone to configure notifications. There are general Alerts properties as well as inside each job.

Advertisement

NetApp NDMP with Symantec BackupExec

Some time ago I uploaded a bunch of photos from the data center, where you can find our backup setup. We connect Sun StorageTek SL500 tape library directly to NetApp filer to perform backups of the virtual infrastructure using NDMP protocol. As opposed to LAN backup, NDMP allows you to offload LAN from backup traffic. Look at the following picture:

Here BackupExec only sends NDMP control commands to NDMP host, which in its turn send data to directly attached tape library. We use slightly more complicated 3-way backup architecture:

We have two filers in high availability cluster. And each of the filers has its own hard drive shelves and data. Filer under number 3 on the picture is the primary source of backup data and data from filer 2 is backed up occasionally. Since filer 2 has no connection to the library, when backup is initiated it is send via LAN from filer 2 to filer 3 and then to the tape library.

NetApp configuration

NDMP configuration involves several steps. First of all enable ndmpd on NetApp and set version 4, which Symantec BackupExec works with:

ndmpd on
ndmpd version 4

Then it’s a generally good idea to restrict NDMP access only to particular hosts and interface, because by default access is allowed from anywhere. In our setup NDMP traffic goes through completely isolated management network. We added two IP addresses to allowed hosts. First is the backup server and second is the partner filer:

options ndmpd.access hosts=ip_1,ip_2
options ndmpd.access if=manage_if

Then I’d recommend to create separate user for NMDP backups, change its group to Backup Operators and create special ndmp password which you will use to connect from BackupExec:

useradmin useradd backup
useradmin user modify backup -g “Backup Operators”
ndmpd password backup

As a last recommendation I suggest changing preferred network interface for data connections. By default for data traffic filer uses the same network interface from which it receives control commands. But if you have separate network for filer to filer communications its preferable to use it. In our configuration it’s the same management interface so for us it doesn’t make any difference:

options ndmpd.preferred_interface manage_if

Additionally you can use the following command to list your tape library robots:

storage show mc

Do the same configuration for all filers, if you have more than one.

BackupExec configuration

For NDMP to work in BackupExec you should obtain a licence key and install NDMP Option module. Then go to Devices section, click Add NDMP Server. In Add NDMP Server dialog box specify server name and logon account. If you have more than one filer, do it for each one.

That’s it. Now you have filer volumes in backup selection lists, tapes in Media section and you are ready to do backups.