Category Archives: Storage

Expanding the Disks on Exchange Databases

This article outlines few tips of extending the storage of exchange servers where it hosts the database and log files.

For physical Server:

Add new disks in the RAID hard-drive bay and use array management utility to install the new disks to  the existing Raid.

Then expand Raid size (using Raid utility) for these disk which needs to be expanded. After this in the Raid config utility we see the extra space.Most of the SAN systems has the option to dynamically extend the disk space allocated for the servers.

So we can check the below thing using the storage management utility that we have based on the type of RAID and storage we have (eg. netapp)

• Checking initial status of the existing drives to make sure they are healthy.
• Inserting new Hard Drives in the available slots in the hard drive bay.
• Check the Status of the new drives in the storage array management utility.
• Initialize the new disks and make it available.
Then use Disk-part and extend the disk in the windows on the Exchange hosts.

Example for extending the presented disk :
Open command prompt, type: Diskpart.exe
In DISKPART prompt, type: Select Volume 1 (Selects the volume.)
In DISKPART prompt, type: Extend Size=50000 (If you do not set a size, in example like 50GB set it will use  all of the presented size).
In DISKPART prompt, type: Exit.

Using Disk Part does not affect the system accessing the data and can be done anytime.

For VMWare:

Expand the volume size of Exchange database partition from the vSphere client.
After this the additional space will be reflected immediately on the Exchange servers on diskmgmt.msc.

Expansion of the Exchange database or log drives  in VMWare is seamless however to be safe its always recommended to have a good backup in place before making this change.

Extend the database partition on the VMWare.
Extend the Presented disk in disk management.
If the disks are assigned for VM make sure they are thick provisioned.

Most of the hosted LUNs (eg like from netapp and others) can be grown and shrunk without a single problem on the application side and other vendors are the same.

Using Disk Part does not affect the system accessing the data and can be done anytime.

For hyper v :

Switch-over all databases to one server.
Shutdown the server.
In Hyper-V, increase the disk size of all database disks.
Start the server.
After this we need to Expand the Disk in the disk manager before you move the databases back.
Move the databases back to the activate on preferred node.
Repeat for the remaining servers.

Additional tips:

1) If the primary Mailbox database is increasing its better to have a de-duplication archival solution in place which will manage the storage increase efficiently.
2)Make sure all the new presented exchange drives are MBR formatted.
3)If we are extending the disks for DAG then we need to extend the disks for all DAG members hosting the copies.
4)In larger deployments where we host multiple copies in DAG its always better to have the database disks aligned in the Mount Points only.
5)Dynamic expansion of the VHDx files are supported. Older method of Dynamically expanding VHD’s not supported.
6)Always use the file system as REFS for Exchange 2016 only for Exchange DB’s & logs. Use NTFS for Exchange binaries.
7)Microsoft recommends to use the partition structure as GPT since GPT Is a newer standard  supporting up to 128 partitions in windows and is gradually replacing MBR. MBR type partitions are still supported. MBR only works with disks up to 2 TB in size
8)Better to have a healthy backup before starting these procedures.
9)For VMWare partition expansion ensure that these VM’s are not in snapshots before extending the VMDK files.
10)Better to perform this operation on a low I\O operations period on the array.
For DAG members better to expand the disks one by one on their copies see the results and then proceed.

Thanks & Regards
Sathish Veerapandian
MVP – Office Servers & Services

Exchange 2010/2013 Mailbox Quota , Message size planning for end users

In this article i’m giving some best suggestions that can be scoped in-terms of storage  for any new implementation and redesigning of existing environment for Exchange messaging Platform.

There is no such in recommendation of giving a standard best practice for mailbox size, Maximum message size , retention and archive  as it varies according to each every org structure based on Storage , Email flow per day , Server hardware , memory, requirement  etc..,

Before taking up any new implementation its always better to set up scope on the below things

1) Mailbox Size per user.

2) Maximum Size of Message.

3) Retention of Mailbox items.

The first step we will look in planning mailbox size for users
The better way i would suggest is to first collect the daily, weekly and monthly email statistics for the whole environment

These amazing scripts from nuno mota will help you on collecting the statistics which is very useful.

Emails sent per hour

Emails sent per day and size

Emails sent per week and size

Calculate the average size of the emails sent per user on daily basis from the above output

Based on that calculate the mailbox quota that you need to set for all the users .
You need to make sure that all the mailboxes are balanced equally on existing mailbox servers before planning.
Measure the currently allocated disk size in each mailbox server based on the current value and expected value in 1 year.
multiply the value and calculate the growth of expected users in 1 year.
Calculate the current log space , database space and the expected value after 6 months
Always keep a buffer value of 30 percent on the total value of the disk space required to be on the safer side.

Better you can set some exclusions for mailbox quota for  VIP users.When we say VIP users you can better define a policy with the client before taking up the project. Example for executive users the mailbox size will be unlimited and for the number of users and fix a static value for the remaining mailboxes and finalize the agreement. Define these policies clearly before taking up any new project.

Because a poor capacity planning will bring the following causes :

1) Increased storage cost as days passes.
2) More network bandwidth usage between servers and clients since all the users will have their emails stored in their mailbox.
3) Affecting the storage subsystem in terms of I/Ops.
2) Maximum message size

Planning for maximum message size for the whole organization is also very important.

Following things can be impacted of improper message size planning

1) First thing will affect you is mass mailing from the organizations itself (HR,Marketing Team). They will start sending mass mails with large attachments if the message size is not restricted properly.Impact of this will be your hub servers will go down.
Always you need to give a clear note of this part during the planning and make a best practice of sending mass mails after production hours since the normal emails will be affected.

2) It increases the network utilization of messaging system which will create again an impact.

3) If the network is compromised by a hacker then he can utilize the network/system resources by sending emails with large attachments.

4) Also it will be difficult for anti-spam solutions to scan these emails with large attachments and more possibly exclude most of the attachments if they are encrypted with large size and no exclusions set for encrypted attachments in the anti-spam filter.

3) Retention and archive

Planning for retention and archive is very important

Also it would be good if you implement some archiving solution in place for emails older than 10 months so that your primary mailbox will not be loaded always and less load on the exchange server.
When you bring up archive make sure that the retention for the archived items is planned properly (depending upon your client suggestion) as few orgs would like to have emails of more than 5 years since the retention of the archive cannot be restored at any cost unless we have alternative solution in that place.

Planning this part and convincing the client is little bit tough and difficult since the cost is involved more in this factor when they say they want to keep the retention items in archive for ever.

Hope this reading is helpful


Sathish Veerapandian

MVP- Exchange Server

%d bloggers like this: