Ill try to give a slighty less sparse overview.
(started writing this before tricky's answer)
Scandisk = fsck
Linux comes with fsck which is a container for apps that check filesystems like fsck.ext, fsck.vfat, etc. On startup Linux automagically checks ure (auto)mounted filesystems on integrity, so u don't need to do that. Only if Linux experiences a "dirty" shutdown due to brownouts or u pressing the pwr button and it can't get up itself cuz some files seem corrupted, then uve gotta run fsck.
Diskdefrag
Even tho there's an app to defragment, ext2 partitions won't need it.
Antivirus
Linux Antivirus products are divided into roughly 2 kind of apps. "Regular" AV products and MTA related products.
The MTA (Mail Transfer Agents) related AV products scan/filter/change f.i. messages for viruses, file extensions, MIME parts of messages etc. for Qmail, Exim, Sendmail before mail is delivered to the user.
Regular AV products are just like any W32 type scanner, some have on-the-fly protection with a running monitor.
Some rough test results u can find on my own
page but basically Ive had bad results scanning my virlibs with HBDEV, Sophos and older versions of AVP. Ive had good results with RAV, newer AVP. The best scanner I recommend is Mcafee's Uvscan.
Security
The amount of passive/active steps to take depend on the usage of the box, but priming post-install security measures should not be bypassed: (not exhaustive) local security on accounts, passwords, various filesystem bits like immutables and set UID, paths, maintaining and checking of integrity, preparing network access denial and filtering.
The best practices are offered in AUS-CERT's document called
UNIX Computer Security Checklist (ftp)
*Remember Linux is way more powerfull in comparison to the std windoze box, read
this, for more go to cert.org, sans.org, securityfocus.com, secinf.net, or search the web for the Linux Administrator's Security Guide (LASG).
Any security related questions are always answered at LinuxQuestions.org Forums > Linux - Security forum.
Registry checkers & ways to view devices including their drivers and properties
Ofcuz Linux dont have no registry :-]. A lot of info can be catted from /proc just like system commands like ls and ps read their info, the kernel doc sez: "The proc file system acts as an interface to internal data structures in the kernel. It can be used to obtain information about the system and to change certain kernel parameters at runtime (sysctl)." Linux comes with a lot of tools, f.i. for info on kernel modules ("drivers") use the modutils package (lsmod etc). If u want some info on what partitions ure HD's got, just do "cat /proc/partitions". The column "major" shows the type (22 for ext2.fs and 3 for vfat), "minor" the partition number and blocks and name speak for itself. This way u can also get DMA usage, interrupts, kernel version, SCSI/bus/USB/IDE usage etc. etc. More tools that automate this like si (system info) can be found on freshmeat.net or rpmfind.net.
Ways to view yur hard disk and find out how much space is still available= df and du
Df summarizes free disk space, and du summarizes disk usage. Tools like Xdiskusage can show it graphically.
HTH
[Edited by unSpawn on 06-13-2001 at 07:05 AM]