External Storage Options
You can use iSCSI, or Network File System (NFS) to provide an offboard storage solution.
Onboard disks provide a low latency and high throughput storage solution, which is tested and validated with various workloads. When multiple appliances are deployed, performance and capacity scale at the same rate.
iSCSI
iSCSI uses a dedicated storage channel over standard Ethernet infrastructure, rather than a dedicated SAN network. For this reason, iSCSI can be the easiest to implement, most cost effective, and most readily available.
If you implement an iSCSI solution, then network capacity is shared between external storage access and management interface I/O. In this situation, you can configure a secondary network interface on a separate storage network.
JSA supports 1 Gbit and 10 Gbit connectivity out of the box on many appliances.
NFS
If you use NFS or a Windows share for offboard storage, your system can lock and cause an outage. This practice is not supported by JSA.
If you choose to use NFS anyway, NFS can be used only for daily backup data, such as the / store/backup directory. You cannot use NFS for storing active data, which includes the PostgreSQL and ariel databases. If you do use NFS, it might cause database corruption or performance issues.
Use NFS for tasks during off-peak times, tasks that involve batch file writes, and tasks that involve a limited volume of file I/O. For example, use NFS for daily configuration and data backups.
NFS storage operates over existing management Ethernet networks and is limited by networking performance. It is possible to use a dedicated network interface to improve networking performance when compared to sharing a management interface. The NFS protocol might affect performance for file access, locking, and network permissions.
If NFS is used only for backups, the same NFS share can be used for each host. The backup files contain the system host name, which enables the identification of each backup file. If you are storing a long period of data on your NFS shares, consider a separate share or export for each appliance in your deployment.
External Storage Limitations
Multiple systems cannot access the same block device in a JSA deployment.
If you configure iSCSI in an HA environment, do not mount the iSCSI volumes on the secondary host while the primary host is accessing the volumes.
An external storage device must able to provide consistent read and write capacity of 100 MBps to 200 MBps. When consistent read and write capacity is not available, the following issues might occur:
Data write performance is impacted.
Search performance is impacted.
If performance continues to degrade, then the processing pipeline can become blocked and JSA might display warning messages and drop events and flows.
Offboard Storage in HA Environments
If you choose to move the /store file system in a high-availability (HA) environment, the /store file system is not replicated by using Disk Replication Block Device (DRBD).
If you move the /store/ariel file system to an offboard storage device and maintain the /store file system on local disk, the/store file system is synchronized with the secondary HA host by using DRBD. By default, when your environment is configured for HA, DRBD is enabled.