In this article we will have a look at extending the Enterprise Vault to DR site. This configuration will be helpful when the main site is completely down.
Usually below will be the Enterprise vault configuration in most of the cases :
1) Active/Passive Configuration on Primary Site.
2) HA Failover option will be present in primary site.
3) EV will be available 100 percent in primary site.
In most cases 99 percent the enterprise vault will be configured in Microsoft Cluster because of Good stability of Windows cluster.
Normal Active/Passive setup with HA option in Main site :
Implications without EV DR :
- Archived items will not be available when the main site is not available.
- EV items stored in EV storage will be not available.
So in a normal scenario where the main site is operational and available the DR server will not be functioning and will remain as Standby.
A typical DR solution requires primary and secondary sites, and clusters within those sites for the EV to function.
There are 2 options available for EV DR setup :
1) Go with update service location option with Symantec software. (Requires more manual operation like below)
a) SQL native tools to DR failover.
b) Mount the volumes of EV stores appropriately.
c) Need to use the EV native Update service Location (USL).
on top of the above we are not sure that the replicated storage of EV data and SQL to DR is healthy or not.
2) Go with an EV aware DR application software.(Recommended)
There are few EV aware software’s available in market. They can fully automate the failover and failback between the sites. Its better to go with this option.
Below are the EV aware software’s which is available :
- Enterprise Vault with InfoScale Enterprise.
- EV Near Sync.
Below is one example of high level design of EV DR setup:
Below is the summary:
1) Have EV Seperate Cluster on secondary site.
2) Perform the SQL and EV storage replication to the DR site regularly.
3) Have an EV aware software which performs the automatic failover and failback in case of disaster.Because these software after the intitial configuration does rest of the work such as updating entries in SQL database and activating the DR replicated Vault storage groups.
4) Need to change the DNS alias pointing from production to DR in case of DR activation.
1) The EV storage groups needs to be replicated to the DR site ,can be done through SAN replication and most of the storage vendors are having the SAN replication.
2) Replication needs to be synchronous from the main site to the DR site.
3) Replication needs to be scheduled from the storage everyday for incremental updates.
4) Replication should be performed after the daily archiving schedule, during the vault stores in backup mode.
5) Indexes, databases, and files from the primary NAS to DR should be synced on a daily schedule.
SQL Replication Requirements:
1) Symantec recommends as a best practice to configure SQL Server for disaster recovery before configuring Enterprise Vault for disaster recovery.
2) A SQL server instance must be present on the DR site for SQL replication.
3) SQL server log shipping must be done to replication of DR.
4) SQL server DB replication must be done for replication to DR.
5) SQL data needs to be replicated in daily schedule to the DR site.
EV server requirements:
1) A new site DR to be defined in the EV topology in the vault admin console.
2) 2 new EV nodes with different names to be introduced in this Site.
3) Volume replication needs to be scheduled after storage is ready on the DR.
4) SQL replication needs to be scheduled after the DR instance is setup.
5) Better to have an well known EV aware replicating software like InfoScale or EVNEARSYNC which is having a good presence in the market because these applications provides RTO & RPO in minutes compared to the native EV failover scenario.
1) SQL replication needs to be done from the main site to the DR site. Required ports needs to be open.
2) Since SAN replication is already in place better to verify for these Datastores for the replication and required bandwidth for the daily incremental data replication in the current nw bandwidth in the DR site.
3) One standby IP for EV url in the DR site and needs to be pointed to this IP during the DR scenario.
High Level – How DR Works :
1) EV DR servers will be always Turned off in normal scenario.
2) During DR scenario EV DR servers needs to be turned on.
3) Present the replicated healthy storage (indexing & partition) to the DR server (Achieved through EV cmdlets)
4) Present the replicated healthy SQL db to the DR server (Achieved through EV cmdlets)
5) Perform failover by changing production alias to DR Server (Achieved through EV cmdlets)
6) Change DNS alias of Archive URL pointing from production to DR EV server and then run USL (Update service location).
All these above steps can be reduced and performed automatically by an EV aware application like EVNEARSYNC or InfoScale Enterprise.
1) The storage SAN replication needs to be planned accordingly with the current storage vendor and their recommendations.
2) Need to make sure the Exchange DR setup is already in place, databases replicated in DR site and should be able to perform Exchange DR activation also to achieve best SLA for Email.
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