Prepare for 2019 Oracle has announced that, effective January 2019, Java SE 8 public updates will no longer be available for “Business, Commercial or Production use” without a commercial license. End of Public Updates for Oracle JDK 8 Is Oracle Java still free? The current version of Java – Java SE 9 as well as Java […]
An unprecedented ‘‘ransomware’’ cyberattack that has already hit tens of thousands of victims in 150 countries over the weekend could wreak greater havoc as more malicious variations appear and people return to their desks Monday and power up computers at the start of the workweek. LIVE Map of WannaCrypt infection WannaCrypt can leave your computer […]
Security Groups are great for managing large groups for permissions. A client requested that they needed to have Read-Only, Read-Write, and Ready-Modify (allow for deleting) for all their file shares for better management. Getting the Share Names In order for me to create the groups I needed the share names. PowerShell to the rescue! Type […]
From time to time I come across this need; where I need to scrub a file where there are duplicates, there are blank lines, the sort order is all wack, and it just needs to be formatted to where it can be more readable and/or usable. This method just doesn’t apply to text, but also […]
Admins need to understand some basic networking concepts like CIDR. These are needed when working with AntiSpam & Archiving providers. Here is a simple chart describing the CIDR subnets.
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32 = X-network-bits + Y-host-bits Addresses = 2 ^ Y-host-bits -------------------------------------------------------------- CIDR Total number Network Description: Notation: of addresses: Mask: -------------------------------------------------------------- /0 4,294,967,296 0.0.0.0 Every Address /1 2,147,483,648 128.0.0.0 128 /8 nets /2 1,073,741,824 192.0.0.0 64 /8 nets /3 536,870,912 224.0.0.0 32 /8 nets /4 268,435,456 240.0.0.0 16 /8 nets /5 134,217,728 248.0.0.0 8 /8 nets /6 67,108,864 252.0.0.0 4 /8 nets /7 33,554,432 254.0.0.0 2 /8 nets /8 16,777,214 255.0.0.0 1 /8 net -------------------------------------------------------------- /9 8,388,608 255.128.0.0 128 /16 nets /10 4,194,304 255.192.0.0 64 /16 nets /11 2,097,152 255.224.0.0 32 /16 nets /12 1,048,576 255.240.0.0 16 /16 nets /13 524,288 255.248.0.0 8 /16 nets /14 262,144 255.252.0.0 4 /16 nets /15 131.072 255.254.0.0 2 /16 nets /16 65,536 255.255.0.0 1 /16 -------------------------------------------------------------- /17 32,768 255.255.128.0 128 /24 nets /18 16,384 255.255.192.0 64 /24 nets /19 8,192 255.255.224.0 32 /24 nets /20 4,096 255.255.240.0 16 /24 nets /21 2,048 255.255.248.0 8 /24 nets /22 1,024 255.255.252.0 4 /24 nets /23 512 255.255.254.0 2 /24 nets /24 256 255.255.255.0 1 /24 -------------------------------------------------------------- /25 128 255.255.255.128 Half of a /24 /26 64 255.255.255.192 Fourth of a /24 /27 32 255.255.255.224 Eighth of a /24 /28 16 255.255.255.240 1/16th of a /24 /29 8 255.255.255.248 5 Usable addresses /30 4 255.255.255.252 1 Usable address /31 2 255.255.255.254 Unusable /32 1 255.255.255.255 Single host -------------------------------------------------------------- |
In networks larger than a /31, one address is used for the network number, another for the broadcast address, and generally another as the default […]
Often times engineers make the fundamental mistake of choosing the wrong type of RAID when a server is setup. When disaster strikes this may leave them with data loss, long backup process, loss of time etc. Its important to choose the right type of RAID when first setting up the server. Its important to identify […]
