Sunday, December 29, 2013

Use iTunes Match to Upgrade Your Music Collection

Use iTunes Match to Upgrade Your Music Collection

  1. Make a backup copy of your music first.
  2. Turn on iTunes Match in iTunes.
  3. Select new location for iTunes Media folder.  Turn on 'Keep iTunes folder organized'.  Turn off 'Copy files to iTunes Media folder when adding to library'.
  4. Add your music (Add file to Library).  Wait for music to be matched in iCloud.  You can right click in the header bar to display iCloud Status column.
  5. After songs have been matched, select all/some of the files and delete the songs in iTunes.  Do not check the box to delete from iCloud.
  6. Select songs and download.  Songs will be downloaded to iTunes Media folder in M4A format.

Motorola Date of Manufacture From Serial Number

Source: http://www.akardam.net/moto/tools/serial4.pl

2nd Letter
Year

3rd Letter
Month
A1976/2000 AJanuary
B1977/2001 BJanuary
C1978/2002 CFebruary
D1979/2003 DFebruary
E1980/2004 EMarch
F1981/2005 FMarch
G1982/2006 GApril
H1983/2007 HApril
J1984/2008 JMay
K1985/2009 KMay
L1986/2010 LJune
M1987/2011 MJune
N1988/2012 NJuly
P1989/2013 PJuly
Q1990/2014 QAugust
R1991/2015 RAugust
S1992/2016 SSeptember
T1993/2017 TSeptember
U1994/2018 UOctober
V1995/2019 VOctober
W1996/2020 WNovember
X1997/2021 XNovember
Y1998/2022 YDecember
Z1999/2023 ZDecember

Thursday, December 26, 2013

FreeNAS Web GUI Not Available / Responding

The following message is displayed when trying to access the web GUI of FreeNAS:

An error occurred.

Sorry, the page you are looking for is currently unavailable.
Please try again later.
If you are the system administrator of this resource then you should check the error log for details.
Faithfully yours, nginx.
 
Solution:
From shell (#9 on console menu) type:
 /usr/local/etc/rc.d/django start
 
Web server should start a few seconds later.
Type 'exit' to return to console menu.

ipconfig Commands


ipconfig
Displays all current TCP/IP network configuration values and refreshes Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS) settings. Used without parameters, ipconfig displays the IP address, subnet mask, and default gateway for all adapters.

Syntax

ipconfig [/all] [/renew [Adapter]] [/release [Adapter]] [/flushdns] [/displaydns] [/registerdns] [/showclassid Adapter] [/setclassid Adapter [ClassID]]

Parameters

/all Displays the full TCP/IP configuration for all adapters. Without this parameter, ipconfig displays only the IP address, subnet mask, and default gateway values for each adapter. Adapters can represent physical interfaces, such as installed network adapters, or logical interfaces, such as dial-up connections.
/renew [AdapterRenews DHCP configuration for all adapters (if an adapter is not specified) or for a specific adapter if the Adapter parameter is included. This parameter is available only on computers with adapters that are configured to obtain an IP address automatically. To specify an adapter name, type the adapter name that appears when you use ipconfig without parameters.
/release [AdapterSends a DHCPRELEASE message to the DHCP server to release the current DHCP configuration and discard the IP address configuration for either all adapters (if an adapter is not specified) or for a specific adapter if the Adapter parameter is included. This parameter disables TCP/IP for adapters configured to obtain an IP address automatically. To specify an adapter name, type the adapter name that appears when you use ipconfig without parameters.
/flushdns Flushes and resets the contents of the DNS client resolver cache. During DNS troubleshooting, you can use this procedure to discard negative cache entries from the cache, as well as any other entries that have been added dynamically.
/displaydns Displays the contents of the DNS client resolver cache, which includes both entries preloaded from the local Hosts file and any recently obtained resource records for name queries resolved by the computer. The DNS Client service uses this information to resolve frequently queried names quickly, before querying its configured DNS servers.
/registerdns Initiates manual dynamic registration for the DNS names and IP addresses that are configured at a computer. You can use this parameter to troubleshoot a failed DNS name registration or resolve a dynamic update problem between a client and the DNS server without rebooting the client computer. The DNS settings in the advanced properties of the TCP/IP protocol determine which names are registered in DNS.
/showclassid Adapter Displays the DHCP class ID for a specified adapter. To see the DHCP class ID for all adapters, use the asterisk (*) wildcard character in place ofAdapter. This parameter is available only on computers with adapters that are configured to obtain an IP address automatically.
/setclassid Adapter [ClassIDConfigures the DHCP class ID for a specified adapter. To set the DHCP class ID for all adapters, use the asterisk (*) wildcard character in place of Adapter. This parameter is available only on computers with adapters that are configured to obtain an IP address automatically. If a DHCP class ID is not specified, the current class ID is removed.
/?Displays help at the command prompt.

Tuesday, December 24, 2013

SyncBack Fast Backup

Source: http://www.2brightsparks.com/syncback/help/index.html?creatingaprofile.htm

Easy Mode/Expert Mode: Using Fast Backup

se-pro-feature The Fast Backup feature is only available in SyncBackSE and SyncBackPro.

SyncBack can make backing up even faster if you choose the Fast Backup option. Read this help page carefully before you continue as there are some important considerations to make when choosing this option. You'll also find some Frequently Asked Questions about Fast Backup below along with some examples.

'Fast Backup' option is displayed when you create or modify a profile and select the option from the tree:

fast-backup

note Some of the descriptions below refer to "Fast Backup data". This is data that is kept by SyncBack to keep track of what has changed between each profile run. It is used internally by SyncBack.

•Do not perform a fast backup: Enable this option to perform a standard backup, i.e. the source and destination will be scanned and compared to decide which files must be copied.

•Perform a fast backup: Enable this option to greatly improve the performance of a backup profile by not scanning the destination. Note that this option is only available when a profile is configured in a certain way (i.e. the source is not being changed by the settings). For more information, including side effects of fast backups, please see the section below.

•Perform a fast backup using the archive attribute: Enable this option to greatly improve the performance of a backup profile by not scanning the destination. This option is different from the one above because it uses the traditional backup method of using the archive attribute of a file to decide if a file should be copied or not. Note that this option is only available when a profile is configured in a certain way. For more information, including side effects of fast backups, please see the section below.

•Keep fast backup data based on the actual destination directory (each destination has a full backup): If this option is unticked then a fast backup works much the same as an incremental backup. This means that only new or modified files are copied from the source to the destination regardless of where the destination is. If you are not using variables, e.g. %DAYOFWEEK%, in the destination then you can leave this option unticked as it will make no difference. This option is not available when using a Fast Backup with the archive attribute.

If you are using variables in the destination then you should consider ticking this option. If this option is ticked then the fast backup works in a different way. It keeps track of which files and folders are in each destination. This means each destination directory will have a complete backup and not just contain the new/changed files.

•Differential backup (do not update the fast backup data): If this option is ticked then a fast backup works the same as a differential backup. This means that only new or modified files since the last full backup are copied from the source to the destination. If you are not using variables, e.g. %DAYOFWEEK%, in the destination then you can leave this option unticked as it will make no difference. For example, if your destination is X:\%DAYOFWEEK%\, and you force a rescan on Mondays, then your Monday backup will be a full backup. Your Tuesday backup will contain new and changed files since Monday, Wednesday’s backup will contain new and changed files since Monday, etc. If the Fast Backup is using the archive attribute then the archive bit is not cleared on the original file when it is copied unless it is a full/rescan backup.

•Delete all the files and folders in the destination before the backup (only if it is not a rescan): If this option is ticked then all the files and folders (just the Zip file if compressing to one single Zip file) in the destination are deleted before the backup is made. The files and folders are not deleted if a re-scan has been forced or is required.

This option is best used when "Keep fast backup data based on the actual destination directory" is unticked. For example, if you keep 7 days worth of backups (using the %DAYOFWEEK% variable in the destination), and force a rescan each Monday, then by enabling this option you'll ensure that the Monday backup contains a complete backup and that the backups for all the other days just contain new/changed files since the previous day.

•Use a different folder for full (rescan) backups: If this option is ticked then you can define which folder should be used for full backups, i.e. where to backup to if there is a re-scan. This can be very useful when you always want full backups to go into one folder, and incremental/differential backups to go into the usual destination folder. If you tick this option then SyncBack will automatically set the full folder to your destination folder. However, it is unlikely this is the folder that you wish to use so you should modify it as appropriate.

For example, if your destination is X:\%DAYOFWEEK%\, and you have it set to rescan on Monday, then you probably want your full backup folder set to X:\1\. This means the full backups will always go into the Monday (1) folder even if you force a rescan on a Friday, for example.

•Force re-scan: Click this button to force SyncBack to scan the destination next time the profile is run. Please read the notes below about the consequences of forcing a rescan when using FTP. If the button is disabled it is either because the profile is not a Fast Backup profile or SyncBack will already be performing a rescan on the next profile run, e.g. the button has already been pressed.

•Force a re-scan when: This lets you define when SyncBack should perform a complete re-scan of the destination. For example, to force a complete re-scan every Monday you would select %DAYOFWEEK% from the list, select equals from the drop-down, and type in 1 (1=Monday, 7=Sunday) in the edit box. See the section below for details on why this may be required and what it does. Please read the notes below about the consequences of forcing a rescan when using FTP. Note that you cannot enter a list of values, for example you cannot use %DAYOFWEEK% and enter 1,3 to rescan on Mondays and Wednesdays. Only one value may be entered. With the sbpro-feature-16x16 Pro version it is possible to use scripting to decide when a rescan should occur, meaning far more complex evaluations can be made (see the IncVar.vbs example script).

Important Information About Fast Backups

Explaining Fast Backups

When you backup files to the destination it is assumed that no other application, or person, will be changing the files in the destination. For example, if you backup your files to another drive you are not going to be editing or changing those backup files (except using SyncBack to replace them as appropriate). Because of this SyncBack should be able to remember what files, and directories, are on the destination without needing to scan it to find out.

How 'Fast Backup' works

First, you need to enable a Fast Backup option on the Fast Backup tab. The Fast Backup option is not available if the profile is configured such that it cannot use the Fast Backup option, e.g. it's a Smart Synchronization profile.

How Fast Backup works depends on whether it's using the archive attribute or not:

•Not using the archive attribute: When the profile is next run, SyncBack will remember which files and directories it copied to (or deleted from) the destination directory. This means the first run of a profile, after Fast Backup is enabled, will take the same amount of time as without Fast Backup enabled. However, for the second and subsequent runs of the profile it will not need to scan the destination directory because it remembers what it did the last time the profile was run.

•Using the archive attribute: Each file has what is called an archive attribute (just like files have read-only, hidden, etc. attributes). Whenever a file is changed the archive bit is automatically set (by Windows), and when SyncBack copies a file it clears the archive bit. So when SyncBack needs to know which files are to be copied to the destination it just needs to see if the archive attribute is set. There is no need to scan the destination. The main advantage to using the archive attribute is that there is no need to keep information on the state of the files (so less disk space is used). It may also be very slightly faster (as it doesn't need to read and save the information on the files).

Using Fast Backup means the scan time is substantially lower (at least twice as fast, often far more) especially if the destination is on a slow device, e.g. networked drive, FTP server, etc.

Rescan with archival backups

If a rescan is done, either by clicking the Force Rescan button or by other means, then when the profile is next run it will scan both the source and destination, compare the files, then copy new and changed files. This has a side effect with archival backup in that it will not copy a file (even if it has its archive attribute set) if the source and destination files are the same. If the profile is run again (so it is not a rescan) then it will scan the source, see the file has the archive attribute set, and copy it to the destination regardless.

Can I use Fast Backups on all profile types?

No. The Fast Backup option is only possible when no changes are being made to the destination by other programs, profiles, or users. This means it cannot be used with backups from FTP or Zip files, synchronization profiles, or profiles that use prompting. It is for backup profiles only.

If you are using archival backups you must keep in mind SyncBack is relying on the archive attribute being set once a file is created or changed and is not reset by anything else other than that profile in SyncBack. Once the archive attribute is set then SyncBack knows the file needs to be backed up. However, some other programs, e.g. other backup software, may also use and reset file archive attributes. You must also be careful not to have more than one profile that copies the same files and resets the archive attribute.

Sometimes SyncBack scans the destination directory even though I've enabled Fast Backups. Why?

There are a number of reasons why SyncBack may scan the destination directory:

•The Force Re-scan button has been pressed for that profile.

•The settings on the Fast Backup tab specify a re-scan should be performed under certain conditions.

•The –full command line parameter was used.

•The fast backup data has been deleted.

•The filters or file & folder selections have been modified.

What options does using Fast Backup disable?

When using Fast Backups you cannot enable the following options in your profile:

•Reset the archive file attribute on files once they have been copied.

•Files cannot be moved (to or from the source), and files cannot be copied to the source or deleted from the source (this option can be used with archive attribute fast backups)

•The destination cannot be watched for file changes.

What side effects are there with using Fast Backups?

If the profile is set to delete destination only files, SyncBack may not know a new file has been created in the destination (see this section for more details).

Because a Fast Backup will not scan the destination (except on the first run after it is enabled for that profile) that means only the changes will be applied to the destination without regard to what is actually on the destination. For example, you could change the destination directory, run the profile, and then only the new/modified files would be copied to the destination (and not all the files as would normally be the case).

This has important consequences when your destination directory is dynamic, i.e. it uses environment variables that can change in value. For example:

•Create a normal backup profile and set the source directory to C:\My Documents\ and the destination directory to D:\Backup\%DAYOFWEEK%\

•Enable Fast Backup for the profile.

•On the first run of the profile (let's assume it's Monday and the destination directory is empty) all the files will be copied to D:\Backup\1\

•When the profile is run on Tuesday then only the new or modified files will be copied to D:\Backup\2\

•On Wednesday new and changed files will be copied to D:\Backup\3\ and so on until Monday.

•When it is run again on the following Monday then only the new and changed files will be copied to D:\Backup\1\

•Enable the option "Keep fast backup data based on the actual destination directory". This will create full backups for each day and not just incremental backups for Tuesday to Sunday.

Or

•Enable the option "Delete all the files and folders in the destination before the backup" and force a rescan on Mondays. There are three ways to do this (using this example):

1. The best and easiest option is to configure the "Force a re-scan when:" settings to force a re-scan every Monday (select %DAYOFWEEK% from the list, select equals from the drop-down, and type in 1 (1=Monday, 7=Sunday) in the edit box).

2. You can do this manually by clicking the Force Re-scan button on the Mondays.

3. Use the -full command line option (for Monday only when scheduling).

This will mean that the Monday backup is a complete backup, and the backups on Tuesday to Sunday contain just the new/changed files since the previous days backup.

What about FTP and Fast Backups?

One of the benefits of using Fast Backup and FTP is that it can really improve the backup time. Apart from not having to scan the FTP server to find changes, SyncBack also does not need to set the date & time of the file on the FTP server to match that of its equivalent file on your PC. This can further reduce the backup time.

The Archival Fast Backup option is not available when doing multi-zip backup to an FTP server. When multi-zip files are stored on an FTP server SyncBack must name the Zip files in a special way (to store information like their uncompressed size, for example). Because of this the destination must be scanned to know what those filenames are. The non-archival Fast Backup method can be used (in most cases) because it knows what the destination filename is without scanning (because it is in the fast backup database). However, if the destination folder is dynamic, e.g. it is using a variable, then it can cause problems as it will not always be able to know what the destination filename is.

If you don't care if the date & time of the files on your FTP server match those on your PC then you can untick the "If the FTP server cannot set a files date & time then change the local files date & time to match that on the server" option on the FTP tab.

There are important consequences to doing this: the date & time the file should be set to (on the FTP server) is kept in the Fast Backup data. Therefore, if you force a re-scan (so erasing that data) then the last date & time information is permanently lost. What does this mean?

•When you do a restore all the files will be retrieved from the FTP server along with their last modification date & time, which is not the original value. As the date & times won't match, all the files will be restored unless you've configured your profile to ignore file date & times.

•When you next run a backup all the date & times will be mismatched so forcing a complete backup (unless you've configured your profile to ignore file date & times).

What about backup to a single Zip file on an FTP server?

Making a backup to a single Zip file on a remote FTP server creates some interesting challenges:

1.To update a remote Zip file it would need to be downloaded, updated, and then uploaded. Depending on the size of the Zip file, this could be extremely slow.
2.To know what files and folders are in a remote Zip file it would need to be entirely downloaded.

Because of this SyncBack will always replace the existing Zip file and therefore assume there are no files in the remote Zip file. The solution is to use a Fast Backup profile, i.e. an incremental or differential backup. For example, to keep 7 days worth of backups, and have a full-backup on Mondays and incremental backups on all the other days of the week:

•Create a backup profile and configure your source as appropriate, and set your destination as appropriate (i.e. a single Zip file on an FTP server)

•Set the Destination to something (the %DAYOFWEEK% is required) like \My Backups\%DAYOFWEEK%.zip

•Go to the Fast Backup tab and enable the options: Perform a fast backup and set the full-backup folder to \My Backups\1.zip

•In the "Force a re-scan when:" box select the %DAYOFWEEK% item, select Equals from the drop-down list to the right of the box, and enter 1into the box to the right of the drop-down list (we use 1 because Monday is day 1, Tuesday is day 2, etc).

•You should schedule the profile to run just once every day

Note about "Delete all the files and folders in the destination before the backup"

This option should be used with care because it will delete all the files and folders in the destination before running the profile. However, if you are compressing to a single Zip file it will just delete that Zip file and no other folders or files.

An important detail to remember about this setting is that the destination files are not deleted if the profile run is doing a rescan. For example, if you've configured your profile to rescan on Mondays (%DAYOFWEEK% equals 1) then when the profile is run on a Monday it will not delete the destination files. However, it will delete them if there is no rescan. This has consequences if you run your profile more than once and also if you do not ever do a rescan. For example, if you configured your profile to rescan on Mondays then when the profile is run on a Tuesday it will delete the destination files and copy over the new or changed files since the last profile run. However, if you run it again immediately (and assuming it is still Tuesday) it will delete those files and then copy over any new or changed files since the last run, which may be no files at all.

Versioning

As an alternative to doing incremental or differential backups, you may want to consider using Versioning instead. With versioning you can keep a defined number of versions of a file. This means you can keep old versions of files that have been changed or deleted. Note that you can use versioning with Fast Backup, but it can become complex and will slow down a Fast Backup (as SyncBack must scan the destination to know what versions are available).

Example Fast Backup Configurations

The following section provides example backup configurations.



To keep 7 days worth of backups, and have a full-backup on Mondays and incremental backups on all the other days of the week:

•Create a backup profile and configure your source as appropriate

•Set the Destination to something (the %DAYOFWEEK% is required) like D:\My Backups\%DAYOFWEEK%\

•Go to the Fast Backup tab and enable the options: Perform a fast backup and Delete all the files and folders in the destination before the backup, and set the full-backup folder to D:\My Backups\1\

•In the "Force a re-scan when:" box select the %DAYOFWEEK% item, select Equals from the drop-down list to the right of the box, and enter 1into the box to the right of the drop-down list (we use 1 because Monday is day 1, Tuesday is day 2, etc).

•You should schedule the profile to run just once every day



To keep 7 days worth of backups, and have a full-backup on Mondays and differential backups on all the other days of the week:

•Create a backup profile and configure your source as appropriate

•Set the Destination to something (the %DAYOFWEEK% is required) like D:\My Backups\%DAYOFWEEK%\

•Go to the Fast Backup page and enable the options: Perform a fast backup, Differential backup (do not update the fast backup data), Delete all the files and folders in the destination before the backup, and set the full-backup folder to D:\My Backups\1\

•In the "Force a re-scan when:" box select the %DAYOFWEEK% item, select Equals from the drop-down list to the right of the box, and enter 1 into the box to the right of the drop-down list (we use 1 because Monday is day 1, Tuesday is day 2, etc).

•You should schedule the profile to run just once every day



To keep 7 days worth of backups and have full-backups for each day:

•Create a backup profile and configure your source as appropriate

•Set the Destination to something (the %DAYOFWEEK% is required) like D:\My Backups\%DAYOFWEEK%\

•Go to the Fast Backup tab and enable the options: Perform a fast backup and Keep fast backup data based on the actual destination directory

•Go to the Decisions - Files page and configure the profile to delete files from the destination that do not exist on the source. This ensures that your backups don't get cluttered with redundant files.

•You should schedule the profile to run just once every day



To keep full-backups on a set of disks:

•Create a backup profile and configure your Source as appropriate

•Set the Destination, e.g. X:\%SERIAL%, where X: is a drive that accepts removable media, e.g. a CD/DVD drive, Zip drive, floppy disk drive, etc.

•Go to the Fast Backup tab and enable the options: Perform a fast backup and Keep fast backup data based on the actual destination directory

•Go to the Decisions - Files page and configure the profile to delete files from the destination that do not exist on the source. This ensures that your backups don't get cluttered with redundant files.

•Each time you run the profile use a different disk. You could keep 10 days worth of backups by rotating a set of 10 disks. Each disk will have a complete backup.



All Content: 2BrightSparks Pte Ltd © 2003-2013

Incremental Versus Differential Backups

Source: http://www.backupcritic.com/software-buyer/differential-incremental.html

Incremental Versus Differential Backups

Even a casual home computer user can accumulate some pretty large amounts of data that need backing up. People may mail you large attachments that contain spreadsheets or big documents, making your mailbox bigger and bigger over time, for example. Even just the common hobby of taking digital photos can quickly make your disk space requirements mount up.
Differential and incremental backups are easy ways to reduce the time and space requirements of backups, which may encourage you to backup more often. This benefit increases when you want to keep multiple backups of the same data. For example, instead of just backing up all your files to a recordable DVD disc every night, you could back it up onto seven different discs -- one for each day of the week. That way, if you realized on Friday that you accidentally deleted an important section from a document back on Tuesday, you could just pull out the backup disc labelled "Monday" and restore that particular version of the document, even though you've made other changes to the document in the days since then.
Incremental and differential backups mainly show up in file-based backup software, notimage backup software. There are exceptions to the rule, however, and I'll talk about that below.

Incremental Backup

Incremental backup just means only backing up data that changed since the last backup. Incremental backups can be a great way to save space and yet retain multiple versions of changed files. I'll give you an example to make this clear.
Remember the example I gave earlier about using seven backup discs, one for each day of the week? Suppose that a full backup requires 20 minutes to burn to a recordable DVD disc. You can cut that time down significantly by using incremental backups.
With an incremental backup scheme, you might decide to make a full backup only on Sunday. On all the other days of the week, you could just do an incremental backup, which means only backing up the files that have changes since the previous backup. Because probably only a small percentage of your backup data changes on any given day, So, instead of 20 minutes to burn a backup, your Monday through Saturday backups might just take 5 minutes each.
This incremental backup scheme can also give you a rough record of when files changed. Each of the incremental backup discs only contains files that changed that day, so looking back through the discs shows you what files changed on which days.

Differential Backup

One drawback of the incremental backup comes if you need to do a full restore. Once again, suppose you're following the full backup on Sunday, incremental daily backup scheme I described earlier. But now suppose your hard drive dies on Friday; consider what you would have to do to restore all your backed-up files.
Obviously, your most recent full backup was on Sunday, so you restore that first. But you also have to then restore each of the most recent incremental backup discs since Sunday: Monday, Tuesday, Wednesday, and Thursday. That may not be too bad, but what if you were keeping a month's worth of incremental backups and not just a week? Having to restore from 30 different incremental backups could be nearly as depressing as having your hard drive die in the first place.
Enter the differential backup, which is quite similar to an incremental backup. The difference is that an incremental backup catches files that have changes since the last backup, but a differential backup catches all files that have changed since the last fullbackup.
So now, consider a scheme in which you want to keep a month's worth of backups. You could perform a full backup only once, on the first of the month, and incremental backups every other day. But to avoid the prospect of having to restore from 30 different discs if there's a hard drive crash, just make one change to these scheme: perform a differential backup instead of an incremental backup on the 7th, 14th, and 21st of the month.
What happens if you have to do a full restore on the 23rd of the month with this revised scheme? First, you restore from the initial, full backup from the 1st of the month. Next, you restore from the differential backup you made on the 21st of the month; remember, that backup has everything that changed since the last full backup. Finally, restore from the incremental backup made on the 22nd of the month. That's just restoring from 3 discs instead of from 22, a vast improvement.

Shopping For Incremental/Differential Backups?

Should you look for this feature when shopping for backup software? Well, the casual home user probably doesn't need a complex scheme of storing different backups for every day of the month, but since even sub-$50 backup software often provides some kind of incremental backup, it's worth looking for it.
Note that there is no universal agreement on terminology or functionality here, so you have to look at a package closely to see whether it offers incremental or differential backups, and just what form that takes. For example, if software lets you say "backup all files that have changed since ", then you can use that feature to create differential or incremental backups yourself (by remembering when your last backup/incremental backup took place) even if the software has no direct support for them.
The form this feature takes may also depend on other aspects of the backup software. For example, higher-end software may assume that you are backing up to another hard drive or other spacious medium, and may let you set up completely automated, complex schemes that require little extra effort on your part (e.g., no labelling and filing recordable discs).

Incremental Image Backup

Although less common, some image backup software also offers a feature like incremental backup. However, since it is a disk image being backed up and not individual files, you most commonly have only the option to restore the entire disk to a previous backup point, not individual files.
If you take incremental image backup to the extreme, you get what is sometimes called "Continuous Data Protection". With this kind of software, every little change that happens to your hard disk is being backed up in real time to another disk (usually onto another computer, across a network).
Another variation of this scheme involves tracking every low-level disk change right on the same hard disk. That gives you the ability to "roll back" your disk to the state it was in at any given point in the past. This is not necessarily the best kind of backup, but is very useful in special situations, such as testing new software; after installing and testing a software package, you can rollback the disk to its original state so you can test again.

Sunday, December 22, 2013

Cisco WS-C3750X Model Numbers

Cisco WS-C3750X Model Numbers

With LAN Base Software

FeatureWS-C3750X-24T-LWS-C3750X-48T-LWS-C3750X-24P-LWS-C3750X-48P-LWS-C3750X-48PF-L
Total 10/100/1000 Ethernet Ports244824 Power over Ethernet Plus (POE+)48 POE+48 POE+
UplinksModular 4 x 1 GE, 2 x 10 GE, 2 x 10GB-T,
and Service Module with two 10 GE SFP + Interfaces
Default AC Power Supply Rating with Dual Modular Slots350W350W715W715W1100W
Default Power over Ethernet (PoE) Power--370W370W740W
Stack PowerYes
Available starting with Cisco IOS Release 15.0.(2)SE. 
StackPower cable purchased separately.

With IP Base Software

FeatureWS-C3750X-12S-SWS-C3750X-24P-SWS-C3750X-24S-SWS-C3750X-24T-SWS-C3750X-48P-SWS-C3750X-48PF-SWS-C3750X-48T-S
Total 10/100/1000 Ethernet Ports12 SFP24 POE+24 SFP2448 POE+48 POE+48
UplinksModular 4 x 1 GE, 2 x 10 GE, 2 x 10GB-T, and Service Module with two 10 GE SFP+ Interfaces
Default AC Power Supply Rating with Dual Modular Slots350W715W350W350W715W1100W350W
Default PoE Power-370W--370W740W-
Stack PowerYes

With IP Services Software

FeatureWS-C3750X-12S-EWS-C3750X-24P-EWS-C3750X-24S-EWS-C3750X-24T-EWS-C3750X-48P-EWS-C3750X-48PF-EWS-C3750X-48T-E
Total Gigabit Ethernet Ports12 SFP24 POE+24 SFP2448 POE+48 POE+48
UplinksModular 4 x 1 GE, 2 x 10 GE, 2 x 10GB-T, and Service Module with two 10 GE SFP+ Interfaces
Default AC Power Supply Rating with Dual Modular Slots350W715W350W350W715W1100W350W
Default PoE Power-370W--370W740W-
Stack PowerYes