Windows Requirements
The following supplemental information helps your configuration operate correctly and within ideal performance parameters:
- CPU cores:
- Single-core systems can execute only one simultaneous thread and are prone to bottlenecks.
- Simultaneous thread execution is mandatory for acceptable performance from a modern computer.
This misconfiguration is common with virtualized scanners. Make sure that you allocate multiple cores with virtualized scanners.
- Virtual memory paging file size:
- Without virtual memory, it’s necessary to have an excessive amount of physical RAM to avoid out of memory errors.
- Even with a large amount of physical RAM, if the node has zero virtual memory configured, it can encounter unforeseen events, because no systems programmer expects zero virtual memory.
- Enough virtual memory must exist to encompass a complete dump, if the node has a bug check.
Network Requirements
Use the following network requirements as best practice configurations for optimal performance:
NOTE: If the scanners are virtualized, make sure that the configuration of the virtualized networking environment (hypervisor internal software switching/routing), is correct.
- Accurate A and PTR records
Filers and scanners must be provisioned in both forward and reverse DNS lookup zones. Each filer node must have accurate 'A' and 'PTR' records in DNS. When configured correctly, the following DNS operations resolve correctly:
- Command: nslookup.exe hostname.domain.tld
Expected Return: x.x.x.x
- Command: nslookup.exe x.x.x.x
Expected Return: hostname.domain.tld
Where hostname.domain.tld is the Fully-Qualified Domain Name (FQDN) of the filer
Where x.x.x.x is the IP address of the filer
- HOSTS files must not be used for DNS resolution between filers and scanners
HOSTS files are often incomplete and using the HOSTS file for resolution can disrupt or prevent communication. If there’s a special circumstance that requires the use of HOSTS files, make sure that you maintain them regularly. If you’re unsure about your configuration, locate the HOSTS files on the filer and the scanner. Also, make sure that the HOSTS files contain no filer or scanner entries. The location of the HOSTS file on the filer depends on the filer operating system. The location of the HOSTS file on the scanner is the folder %SYSTEMDIR%\System32\Drivers\Etc.
- Make sure that there are no router hops between filers and scanners
The number of router hops between filers and scanners must be zero, with only bridges or switches between the filers and scanners. Each router hop can incur another 1–5 ms of scanning time. With enough hops, this additional time could cause poor performance. Run a traceroute on each filer to each scanner it’s registered with, and each scanner to each filer it’s registered with, and record the hops.
- Make sure that there’s proper IP addressing
To assign the scanners' IP addresses, use one of the following two methods:
Static Addresses:
- Assign static IP addresses to all scanners. It prevents the scanner from inadvertently changing IP addresses.
- Make sure that static IP addresses aren’t within the range of any DHCP address pool.
Static Leases:
- Assign static DHCP leases, via MAC address, to all scanners. It prevents the scanner from inadvertently changing IP addresses.
- Static leases prevent a non-ENSSP device from being assigned an IP address intended for a scanner, causing duplicate address issues.