First post - Asking for advice

Hi all,
For work and personal reasons I have decided to try to learn Java. I don't have much experience with computer languages - just the BASIC I learnt at school 20 years ago and messing around with VBA in Excel.
To start with I'd just like to ask for advice so I hopefully start in the right way.
Firstly, I have downloaded an online book by Bruce Eckel called 'Thinking in Java'. Does anyone have an opinion on if this is a good source to learn from, and if not, a recommendation?
Also, is it best to get an IDE, or just use Notepad to start with?
Lastly, are there any conventions for where to put 3rd party packages and my own code? I'm thinking specifically of the code that comes with the Bruce Eckel book unless anyone puts me off learning from it.
Any other advice for someone starting out would also be greatly appreciated.
Thanks for reading, and I hope I won't be asking too many dumb questions as I go along.
Gary

In the hope that it will save typing out long paths,
I've created a new folder in the c drive (called
Java), with 2 folders inside that - one for 3rd party
libraries (if that's the right word),which I've
called lib (is that bad?) and one for my code (code).
I'm sure it will grow but I'm hoping that will be
enough for me to start learning.lib and code are fine... I use tools and projects respectively at home, but it really doesn't matter that much. What does matter - if you are interested in handling things somewhat fundamentally - is this. You are going to be building and running, setting classpaths, referring to that libs folder etc from command line scripts (batch files) or build scripts (like ant). That location will at some point change, so you want to make your scripts flexible and define that path in only one place. For the same reason, relying on the CLASSPATH environment variable is often discouraged.
At first you'll probably not be using scripts but just type the commands on the console, that's fine, just at some point you'll get tired of typing the same things over and over :-)
The packages that come with the Bruce Eckel book (which are all in a folder called COM) If I'm not mistaken, com would be the root package folder for Eckel's source, as in for example package com.bruceeckel.util. To keep it separated from other libraries which may also have com as first package part, I'm thinking that folder com should be e.g. here:
C:\Java\libs\ThinkingInJava\com
C:\Java\libs\ThinkingInJava\com\bruceckel\util\I hope I'm not confusing you now, but in the long run you will be glad if your libraries are organized properly. The meaning of packages and their relation to folders is explained in Eckel's book so it will become clear.
As for getting there, you seem to have the right attitude, good luck and have fun!

Similar Messages

  • CAN I OVERBURN ??? (strange this is the first post asking for it...)

    Hello all you Mac gurus. Today's question is:
    -> can I OVERBURN? <-
    For those who never heard the term: overburning is the use of high capacity cds like the TDK one I have here in front of me and which theoretically could give me up to 800MB or 90mins of space and time. But overburning also lets you get out more than the actual 700MBs out of the usual CD-Rom, sometimes even 15 to 20 MBs more.
    Hardware: I have a Matshita UJ-846, aka "Superdrive" that came with my brand new PowerBook 1.67GHz 17" HD.
    Apparently NOBODY asked for this before, although the word "overburn" occurs here and there in these forums.
    Frankly I think this is strange - how many films or other data do you have that just do not fit on the 700MB CDs from the drugstore? And how nice could it be to get those two or three 798MB DVD rips onto one CD instead of keeping it on your harddrive?
    BTW I tried DragonBurn - doesn't work - and also FireStarter - doesn't work either. Both tell me that my drive is not supported. But I would hate to give up.
    Thanks!
    PS: a question for those with historical memory: is it possible that Apple does not actively support overburning? It's a nice feature that a lot of pee-cees can use (even the really scrappy one my girlfriend has bought last year). So why on earth can WE not???
    PowerBook G4 17" 1.67 HD + G4 QS 867   Mac OS X (10.4.6)  

    Dear Don,
    thanks for your answer. As you probably know, the term "overburn" is a very common term in the Windows world. There are several softwares out there for us Mac users that allow, at least theoretically, to overburn a disk = to put a certain percentage more of data on a CD-ROM or a DVD than what the factory declares it might contain (for example Dragonburn or FireStarter).
    My issue (and thus my question) here is a different one.
    I have not been able to "overburn" yet with neither of the two above mentioned softwares, even though they both declare it would be possible.
    Perhaps I should have asked in a more specific way - so let's do it now:
    - is it possible to overburn on a Mac tout-court? Is the Mac software AND hardware environment "open" enough to do allow this? In other words: DOES APPLE at least unofficially SUPPORT OVERBURNING?
    - if it is possible, HOW do I do this, and which media can I use?
    The second question is triggered by the fact that I bought several 800MB CD-ROMs (so called "High Capacity") from TDK and SONY. Both above softwares signal that my drive is theoretically capable of overburning. But once I start the process - eg. trying to burn an .avi-compressed film of 760MB on an 800MB TDK or SONY CD-ROM - both softwares say that I have only 91 MB available on the CD. Apparently the MacOS does not RECOGNIZE the CD's full capacity.
    And, again, it seems strange to me that I am the first to ask for this. I presume a lot of people are having similar problems - and the existence of the two softwares I mentioned DO prove that there is a demand for this kind of feature.
    Thanks for an answer!

  • Asking for advice--for beginning (but artistic) photographer.  Recommend Lightroom 5 or Photoshop Elements 12 (Windows 7 OS)?

    Asking for advice--for beginning (but artistic) photographer. Recommend Lightroom 5 or Photoshop Elements 12 (Windows 7 OS)?

    MarwanSati your install log appears to be free of errors.  I would recommend you post your inquiry about accessing this feature within the Photoshop Elements forum.

  • Asking for advice on adding products with descriptions to webpage

    I am a web design and dreamweaver newbie and am in my very limited experience, working on creating a virtual mall.  I'ts something I always wanted to do...go figure..lol.  I do have a lot of companies that will advertise and I have access to their Java and HTML links. I have created (in my mind...lol) I pretty decent start on a homepage from a free template and I want to create pages with pictures and descriptions but I am not sure the best way to go. I cannot afford to have a pro do this for me so I am fishing for some good advice.  I know about creating tables but I hear that tables are so 90's and dreamweaver can do it better in a different format. I have looked through the forums for advice but not have found what I am specifically looking for.  The way I have it from the homepage is that I have links to product types in the content portion of spry accordian and created pages akin to my homepage to display them but from there...not sure.  I do not have a lot of available free time, hardly any to be honest, so if anyone can point me in a good direction or have any good ideas, I would really appreciate it.  Here are my questions:
    1.  Is there a better method to display products besides tables in CS4, and if so, how would I best proceed?  The idea is 3 columns and 4 rows of products with descriptions underneath.  The links provided by the companies would take them to the company website to purchase. I didn't want to alarm the companies by posting a site without some products available but I need some help.
    2. Is it possible and if so, is it a good idea to add a spry tabbed panels into the content portion of the spry accordian?  Would I have to establish an editable region or something specific to allow it to be functionable?
    Separate Question:
    1. I am not sure if I can even ask this coherently but will give it a shot Does DW have a tutorial on adding some type of flash css or revolving pictures to be built into my header area on the homepage?  I do have DW fireworks and I really want to spruce it up...
    I will load the homepage online today to www.virtmallshop.com.  The product links pages won't be availabe except one to give a reference.  Understand that you all know a heck of alot more about this then me so please be kind!
    Thank you
    D

    For Umlaut, you could probably use phonetic keyboard. Highly recommended.
    Use "Ukelele" to create keyboard layout and use dead key to map umlaut (like 'u = ü). With phonetic keyboard you can type as fast as with native keyboard (if not faster) and in unlimited number of languages, without re-learning the layout.
    Brackets are quite easy accessible on Apple keyboard.

  • First post, looking for new Demand5 eps

    Hello forum
    As stated first post so keeping it simple. Where is the last Walking Dead episode (25/08) on Demand5 in Catch Up section. It has regularly been accessable by 12pm Monday since season 3 aired but no sign of it today.
    I noticed the new Once apon a time and The Barrior are on and wondered if someone had forgotton to update it.
    Hangnail

    Don't normally add to my own posts without reply but wanted to update.
    I see that channel 5 has replaced the Monday repeat with Under the Dome. Can anyone at BT confirm that this precludes them from showing The Walking Dead.
    Any information, even a head scratch would be something at this point. Thank you

  • Yesterday, i posted asking for help to get a Customer code working. Now the statement is not actually showing what what's its creating.

    I pasted the statement into my form and it didn't have anymore syntax errors but now it is not actually creating the code. i type in the name and a phone number but nothing is happening?
    If you need anymore info please ask. I'm not sure what else to post to help.

    I am trying to Take the first letter from the Company Name/Customer Name and the last 4 digits from the customers phone number. add them together to create our customer code. IE, my name is sam and the last 4 digits of my number are 6770 so my customer code would be S6770.
    here is the code that is under the text field i am trying to use.
    form1.#subform[0].CustCode::initialize - (FormCalc, client)
    Concat(Left(CustName,1) , Right(TextField9,4))
    Heirachy:
    form1
         -master page
              -page 1
                   -(untitiled content area)
         -(untitled subform) (page 1)
              -rectangle1
              -text6
              -CUst.Type
              -CustName
              -SHip.Via
              -CustCode
              -TextField8[0]
              -Text23[0]
              -Text24[0]
              -Text25[0]
              -TextField8[1]
              -Text23[1]
              -Text24[1]
              -Text25[1]
              -CHeckBox2
              -Text26[0]
              -Text27[0]
              -TextFIeld9[0]
              -Line4[0]
              -Text26[1]
              -CHeckBox3[0]
              -Text27[1]
              -Line4[1]
              -Text27[2]
              -CHeckBox3[1]
              -Text26[2]
              -POReq
              -Text22
              -OfficeUseOnly
                   -Text29
                   -Text13[0]
                   -PrintState
                   -Text13[1]
                   -interest
                   -terms
                   -CreditLimit
                   -PriceMatrix
                   -DropdownList1
                   -TextFIeld11[0]
                   -CHeckBox1[0]
                   -CheckBox1[1]
                   -Text15
                   -TextField11[1]
              -DropDOwnList5
              -Deafult.Loc
              -Text28
              -Text15
              -CHeckBox1[0]
              -CHeckBox1[1]
              -TextField10[0]
              -TextField10[1]
              -TextField10[2]
              -TextField10[3]
              -TextField10[4]
              -TextField10[5]
              -TextField10[0]
              -TextField9[0]
              -TextField9[1]
              -TextField9[2]
              -TextField9[3]
              -TextField9[4]
              -TextField9[5]
              -TextField9[6]
              -TextField9[7]
              -TextField9[8]
              -TextField9[9]
              -TextField9[10]
              -TextField9[11]
              -TextField9[12]
    Here is a picture of the form i am trying to make.

  • Asking for advice for Jabber deployment - multi CUCM cluster\AD domains

    I would like some design advice for deploying Jabber and CUPS in our company. We have 2 locations, west coast (SiteA) and east coast (SiteB). Each site have their own CUCM 7.15 clusters, Unity clusters, AD domains (trusted, but not in the same forest).
    At SiteA I have setup CUPS (8.6.3.10000-20) and jabber and have it working great.
    I would like to setup CUPS\Jabber for SiteB, but they need to be able to IM\call\etc to SiteA (And vice-versa).
    SiteA and SiteB both have CUCM LDAP sync turned on, and LDAP directory synced with both domains (although SiteA cannot authenticate to CUCM at SiteB, and vice-versa due to the fact you can only LDAP sync authentication with one domain, CUCM user database contain users from SiteA and SiteB).
    We have SIP trucks setup to pass internal calls and line status(BLF) between the trunks, and can communicate via internal extensions just fine.
    The problem I’m running into is my jabber-config files uses the EDI directory – which can only look at one domain, so I cannot search the other domain. I believe  changing to UDS fixes this, but I understand it would require me to upgrade both CUCM clusters to 8.6.2 - unless I’m mistaken.
    I’m aware the desktop sharing will not work until CUCM is upgraded to 8.6.1 or 8.6.2.
    I’m wondering if anyone has any advice, or can confirm I’m on the right track. Thanks in advance!

    The thing that's important to understand is how CUP and Jabber build the XMPP URI. The URI has a left- and right-hand side; the left is the username while the right is the XMPP domain. CUP uses the LDAP attribute specified in CUCM's LDAP System page, sAMAccountName by default, for the left-hand-side. The right-hand side is the FQDN of the CUP cluster. Jabber must use the same values as CUP when displaying search results. Take note that nowhere in this process does the entire XMPP URI originate from the directory source.
    In your case you have two separate CUP clusters in two separate domains. This won't work because when a user searches for a contact in the directory using Jabber, the client will build the XMPP URI as [email protected]. Even if you got the other domain's user objects into the search results the right-hand-side of the URI would be wrong and the presence subscription would never succeed since the other cluster is in another domain. As such your first task must be to move the CUP clusters into the exact same fully-qualified DNS domain. Once this is done you can use Inter-Cluster Peering to build a larger XMPP network in which all users have the same presence domain. If you intend to do Inter-Domain Federation in the future this must be your public DNS domain, not your internal active directory domain. If you use a non-public DNS domain TLS handshake will never succeed for inter-domain federation requests.
    Once you have Inter-Cluster Peering in place you can use Active Directory Lightweight Directory Services (the new name for ADAM) to front-end both forests. Both CUCM clusters would need to import the full list of users representing both domains and the sAMAccountNames must be unique across both domains.
    Finally, you can instruct Jabber to use UDS and query it's local CUCM cluster which will be able to return a search result from both domains. Since the CUP clusters are peered in the same domain the XMPP URI can be built properly, the presence subscription can be routed to the correct cluster, and life will be good.
    By this point hopefully it's clear that EDI won't cut it since it would be limited to only returning search results from the local forest.
    Please remember to rate helpful responses and identify helpful or correct answers.

  • LJ 1100 Paper Feeder Jammed - Asking for Advice

       My LJ1100 just broke, the drive may have stripped a gear, it makes a buzzing sound and won't pull the paper through. If anybody has an idea on how to  get into the rear where the paper drive is, I would appreciate it. It is not accessible through the toner compartment in the front. Wish I had an IPB. I don't know where to unfasten the back of the box, or if it can be put back together without special tools. The only HP-certified printer shop in the yellow pages for a hundred miles around this smallish city just told me that they stopped fixing printers the first of the month unless you buy an annual contract for on-site service, and I am already stuck with the cost of a new  type 92 toner cartridge that I put in it, 3 days before it stopped printing, so, I am stuck if I can't fix it myself. 
       If you can tell me how to get into the paper-feeder's mechanism, I will try to make the LJ 1100 useable again, and will not need to recycle it for several more years, I hope. Like a lot of people, I am laid off and out of work now, and don't want to buy another one until I can get a job to pay for it. 

  • Asking for Advice

    We are planning on a buying the new 27-inch iMac for the family. I am going through difficulties in choosing between the 2.93GHz Core i7 or the 3.6 GHz Corei5 configuration for the 27-inch iMac. I have read through different posts explaining how CPUs with a lower number of threads(i5), but a higher clock speed would top CPUs with more threads(i7) and lower clock speeds. I understand that in Intel's Turbo-Mode the i7 can reach clock speeds of 3.6GHZ, but I still believe it wouldn't top the i5 that runs on 3.6GHz natively, and boosts to 3.86GHz under specific conditions. I also, read that the i7 is better for the "future" for having 8 thread on a single die. However, I also came across a post about how PC(iMac) needs more RAM to fully utilize i7 with its 8 threads.
    I am a little lost to choose which option is better for us. I only know that I want this iMac to live long, and serve well and be utilized to its fullest potential(I don't wanna pay more for an 8 threads i7 CPU that would only have 2 threads working 80% of the time)
    I would be grateful for any helpful insights or clarifications

    I think, in addition to general purpose computing, this iMac would be heavily used for creating documents and spreadsheets for work. I know that these needs are met with almost any iMac from the new line-up and even older iMacs.
    But this isn't what worries me, what worries me is how long is this iMac going to survive?
    I understand you want to invest wisely. There's more than one way to do that.
    One, you can buy the best Mac you can afford, and hope it will last a long time. It might, or it might not, there's no way to tell.
    Or, buy the cheapest Mac that will meet your current needs, and save your money to upgrade later when your needs change.
    A $100 used G4 would do a nice job of doing what you've described so far.
    That leaves almost all your budget reserved for adapting to the future as needed.
    You could test this theory by buying a used G4, and giving it a try. If it doesn't work out keep it as a back up machine. My iMac just died after 7 years, and I was back up and running in minutes because I had an old G4 standing by, ready to go to work.
    Best of luck!

  • Save Part of Front Panel as picture - sharing VI and asking for advices

    Hi,
    I use LabVIEW 8.2.1. (DSC&RT),
    It is common (at my work) that we want to save some parts of the Front Panel and to add it to the LogBook.
    we usually do PrintScreen and then cut the picture to the boundaries we want using 'Paint'.
    I have created a simple procedure that makes it easier and the user can now select the boundaries of the picture at the Front Panel.
    You can see the 2 VI's attached, (try2.vi is a sub vi of try.vi)
    Open 'try.vi' and press 'select boundaries' button and drag the boudaries with your mouse,
    after you have selected the boudaries, press 'save picture' button.
    I hope there are no bugs.
    Originally I have wanted to use drag and drop, but i didn't really understand what is going on behind the scenes
    when I used it.
    For example - look at the example (at NI Example Finder at LabVIEW) 'Drag and Drop - Multiple Data Types to Start Drag.vi'
    (C:\Program Files\National Instruments\LabVIEW 8.2\examples\general\dragdrop\Drag and Drop - Multiple Data Types to Start Drag.vi)
    (or via typing 'drop' in at the NI Example Finder search)
    1. I don't understand how the 'Drag and Drop Data' (located at the Application Control Palette)
    2. I don't understand the inside terminals of the Event Structure of 'Drag Enter' and 'Drop' -
        for example - 'available data names' and 'accepted?'
       where can I get information help written about any of the Event Structure inside terminals?
       (it does not appear in the Context Help when I enter with the mouse)
    3. Do you have any comments on the VI  I did ?
    4.I am planning to use this VI as a part of Log-In data to a follow-up LogBook Using Mysql as Database and NI sql connectivity toolkit,
       so users will be able to insert information to the LogBook from the Front Panel, and attach pictures of the Front Panel.
      Did anyone here has performed anything similar ?
    If you send me corrections of someting or any other NI item, please send it in a version that I can see it (I use Labview 8.2.1 DSC&RT)
    Sincerely Yours,
    Amitai Abramson.
    Attachments:
    try.vi ‏67 KB
    try2.vi ‏23 KB

    There are examples that come with the database connectivity toolkit so you are going to have to be more specific about your question. Whether you call it a logbook or something else, it's still a database and a database write is a pretty generic opertation. If you need help in the design of the database, then you should say that is what you need.
    The event data is going to change depending on the event and the type of control. Again, do you have a specific question?

  • Error on VF01 posting asking for foreign trade data incomplete

    Hi Experts,
    Would appreciate anyone can help me on the abovementioned matter.
    The transaction SO created is a local trade.
    1) SO created under one time customer for sold to party. Documentflow status = complete
    2) DO completed normally. Document flow status = complete.
    sold to party address maintained is local country address NOT foreign address.
    3) Billing processing VF01 user encountered an error message : Foreign trade data incomplete. Documentflow status = missiong export data.
    Kindly advise.
    Regards,
    Yong Kok Wah

    Hi Yong,
    Check this report, It will clear the Foriegn trade data for the invoice once it is done you can release the invoice to accouting via VF02. But I am not sure whether this fullfills your requirement.
    Note: Test it in test system
    REPORT ZTEST01.
    tables: vbrk.
    data: i_vbrk like vbrk occurs 0,
          wa_vbrk like vbrk.
    select-options: so_vbeln for vbrk-vbeln.
    parameters: testmode as checkbox default 'X'.
    select * from vbrk into table i_vbrk where vbeln in so_vbeln.
    check not i_vbrk[] is initial.
    loop at i_vbrk into wa_vbrk.
          CALL FUNCTION 'ENQUEUE_EVVBRKE'
         EXPORTING
      MODE_VBRK            = 'E'
      MANDT                = SY-MANDT
        VBELN                = wa_vbrk-vbeln
      X_VBELN              = ' '
      _SCOPE               = '2'
      _WAIT                = ' '
      _COLLECT             = ' '
    EXCEPTIONS
      FOREIGN_LOCK         = 1
      SYSTEM_FAILURE       = 2
      OTHERS               = 3
    IF SY-SUBRC <> 0.
    MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
            WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
    ENDIF.
         if not wa_vbrk-exnum is initial.
           clear wa_vbrk-exnum.
           if testmode = ' '.
            update vbrk from wa_vbrk.
            if sy-subrc = 0.
            write:/ 'Foreign Trade Data cleared for invoice', wa_vbrk-vbeln,
            else.
          write:/ 'Errors at database update of invoice', wa_vbrk-vbeln,'.'.
            endif.
          else.
            write:/ 'Foreign Trade Data cleared for invoice', wa_vbrk-vbeln,
          endif.
         endif.
    CALL FUNCTION 'DEQUEUE_EVVBRKE'
      EXPORTING
      MODE_VBRK       = 'E'
      MANDT           = SY-MANDT
        VBELN           = wa_vbrk-vbeln
      X_VBELN         = ' '
      _SCOPE          = '3'
      _SYNCHRON       = ' '
      _COLLECT        = ' '
    endloop.
    if testmode = 'X'.
       format color col_positive on.
           write:/ 'Testmode, no changes made.'.
       format color col_positive off.
    endif.

  • New here to say hello- ask for advice cloning HDD on a T60

    Hi, my name is Adam-I am new here. And yes...I am windsurfer. Hello !
    I have T30 (just selling, T43 (damaged-just beeing fixed) and T60 (I love it !).
    I bought T60 recently and I am just upgrading it step by step. Its 3 GB RAM and T2400 1.83GHz CPU.
    I have just bought 32 GB SSD and 320GB WD Scorpio Black. I want to "copy" - clone ? Win XP Pro and all software on SSD and fit it into main HDD place and my Scorpio will be fitted with caddy to replace DVD. That is what I want to do. I also have 250GB external Toshiba.  But...I have never done this before and I am not IT specialist, also not very experienced with laptops. But I want to do that by myself, mainly to learn and to save some money too. Perhaps I should "clone" my current HDD 100% (software and files) on both SSD and Scorpio and than delete files from SSD ? Or copy all files on external HDD, delete them from current HDD and clone this HDD on SSD ? I would strongly prefer not to install Win and everything from scratch...what should I do and how ?
    Obviously I am looking for easiest, safe way to to that job. Is that better to fit SSD with caddy into ultrabay and clone current HDD and than remove HDD and fit SSD into HDD place or perhaps I should put SSD into external case and clone current HDD with use of USB ? Sorry for so long list of questions...cheers
    moderator note: information added to subject line for clarification.

    Thanks ! In the meantime I can share my observation about WD Scorpio Black 320 GB: It vibrates so horribly (and makes lot of noise) that I am taking it back to shop tomorrow. My T60 vibrates, my hands feel that strong vibration, I can feel my huge, heavy dining table vibrating and its noisy...not acceptable for me. This is business laptop-that is how I use it - and I do not accept that level of vibration and noise    Really disappointed.
    If they (IT shop) accept to take it back , I will probably try Seagate 320 GB or 500GB 5400rpm/8MB...see what happens. I know vibration and noise are very subjective and that is why I made a comparison (same T60, same caddy): my Toshiba 250GB (removed it from case) is much much quieter than Scorpio and makes no any vibration...

  • Web Based Messageboard (JSP, XML, XSLT) - Just Looking For Advice Please!

    I have a general question - I am not looking for any code, just some advice if possible. I am studying on a Masters course and I have been given an assignment to do which I am having difficult getting started. I have worked a lot with Java up until now, however this is the first time I have had to JSP on my course.
    My current assignment is that I am required to create a simple web based message board, using JSP and XML, which allows users to post messages to the board, and also to reply to messages. The content of the message board is stored in an XML file, and there is no database involved. The message data needs to be formatted for viewing in a browser using XSL transformations.
    I am stuck as to how to go about starting the project, and this is all I am asking for advice in. I have created the basic XML file which has some preliminary data stored within it, and I have created an XSL stylesheet to transform this data, however I am stuck with the JSP. Do I need to create a seperate JSP page for each page of the website? How does this link in with the XSLT?
    I would welcome and really appreciate any advice, but I stress that I am not looking for anyone to give me any code or anything like that.
    Thanks.

    You can use XSLT to convert XML to HTML. Then include this HTML in your JSP. Further on you've a plain HTML form with an input field for a message which you submit to a servlet. In the servlet validate/convert/whatever this message and add it to the XML file and then forward/redirect the request back to the JSP.

  • Request for advice configuring/mounting XRAID

    I'm asking for some advice about configuring Xserve RAID.
    I am not an IT person, but just a researcher and have found
    myself in charge of some computing resources.
    We have an Xserve RAID - 14 drive, each set of 7 on RAID5 - connected
    through fibre switch to an Xserve head node. (The fibre switch is
    because we will probably add another Xserve RAID in future)
    The intent for the RAID is to hold our data while we do our computations.
    We have a small cluster of Xserve cluster nodes for distributed Xgrid and
    Matlab computation. I intended to network mount the RAID on each computer
    in cluster. All the users will ssh in to a shell, and none will login to
    a desktop.
    I have just begun to setup the RAID, but ran into some questions that
    I thought I would ask for advice before I proceeded.
    I have already striped both controllers together with software RAID.
    (diskutil createRAID stripe "Journaled HFS+" "RAIDvol" disk2 disk3)
    It created the stripe and created the jHFS+ file system, but I didn't
    realize it would also mount it in /Volumes/RAIDvol
    1. Do people have advice on whether I should keep this mount point?
    I had rather thought I would mount in root (/) on head node and
    cluster nodes, e.g. /RAIDvol instead of /Volumes/RAIDvol
    (And how should I change the mount point? Evidently not through fstab
    - should I use NetInfo(niutil) and is that complicated?)
    Before I change it from mounting in /Volumes, are there any reasons not to?
    (again, no one is going to see a desktop, everyone will ssh into a shell)
    2. Should I have striped the disks together, or concatenated them?
    (What's the difference? - any performance difference?)
    3. Do people have advice on network mounting, AFP vs NFS? What
    performance differences should I consider?
    Thanks for everyone's help.
    dmaus
    Xserve RAID   Mac OS X (10.4)  
      Other OS  

    >1. Do people have advice on whether I should keep this mount point?
    By default all external volumes will mount under /Volumes.
    It is possible to change, but I'd leave it there, it's not worth the hassle trying to bury it somewhere else, and if no one's logging into the desktop then no one's going to notice it anyway. Since it's being shared to the other clients it can be mounted at any point outside of /Volumes, but I'd leave it in /Volumes on the head node.
    Trying to change this will just run into problems later on when Apple change their model.
    >2. Should I have striped the disks together, or concatenated them?
    (What's the difference? - any performance difference?)
    Striping is better than concatenation.
    The difference is in how the volume is laid out, and specifically how the data is written to the volumes.
    If you write a large contiguous file to a striped volume, a chunk of data (32K by default) is written to the first LUN (half of the array) then the second chunk us written to the second LUN). This alternating pattern gives you the best throughput since the RAID is effectively writing to al 14 disks at once, and can be flushing the buffers on the first 32K while the next 32K of data is being written to the other LUN.
    By comparison, concatenation simply appends the second LUN. As you write your file it is all written to the first LUN and it's only when this LUN is full that you start writing to the second LUN. Therefore your throughput is much lower since you're only using half the disks at once.
    Concatenation is easier to setup since some volume formats allow you to grow a volume by simply adding more space at the end, whereas slicing requires a reformat, but those are your choices.
    >3. Do people have advice on network mounting, AFP vs NFS? What
    performance differences should I consider?
    Performance is one factor, security is another. NFS doesn't offer any significant security other than which IP addresses are allowed to mount the volume. AFP supports authentication to ensure that the specific user can mount the volume.
    This may or may not be relevant to you depending on how the clients are mounting the volumes, and whether you want there to be any crossover between the clients. If they're being mounted at startup (so the volume is always available) I'd probably opt for NFS. Home directories, on the other hand, would be better served via AFP.
    Performance wise NFS might have a slight edge, but I've heard others say AFP does, so YMMV.

  • I'm trying to setup my new iphone and the Apple ID it asks for is my friends old Apple ID that she no longer has access to. How can I fix this?

    I'm trying to setup my new iphone and the Apple ID it asks for is my friends old Apple ID that she no longer has access to. How can I fix this so I can use my new phone? The first step asks for my iCloud info but then asks for my friends after I agree to the terms.

    The iPhone is new, has never been used. When asked if I want to set it up as a new phone, restore from an iTunes backup, or my iCloud backup I selected iCloud. It then askes for me to sign in with my Apple ID, I then agree to the terms, then it asks for me to sign into my friends Apple ID. She and I have used each other's computers in the past so I assume this is where her information is coming from. The problem is she no longer had that email or Apple ID and has no way of gaining access to it and therefor I am unable to proceed.
    I suppose my question is, how can I remove her information from mine so I can setup my new phone using iCloud. Also, I have already checked my Apple ID online and nowhere on my account is her information listed.

Maybe you are looking for

  • The Microsoft Access database engine cannot open or write to the file in Report Builder 3.0

    I am trying to build a report in Report Builder 3.0.  I created the Data Source to point to my Excel file and the Data Set.  I drag a couple of fields on to the canvas and then choose Run.  I get the error:  "The Microsoft Access database engine cann

  • "This Apple ID has been disabled for security reasons" Every few weeks

    I have had an iTunes account for years with no issue. Lately, I have been receiving the dreaded "This Apple ID has been disabled for security reasons" message every few weeks on my iPad 2(currenly, my only iOS device). I go through the process of rea

  • MacBook Pro 2008 crashes constantly with Yosemite

    Hi! I'm running an early 2008 15" MacBook Pro with 2,4 GHz Intel Core 2 Duo processor and 4 GB memory, and I just installed Yosemite 10.10.2 as well as the 4 GB memory and a new Samsung 840 EVO SSD 250 GB hard drive and now my computer crashes freque

  • Item category re-determination

    Hi all, I have a requirement to switch the item category from the default value to a new value depending on certain Z fields value at the line item level during sales order creation. I am able to switch the item category to the intended values, howev

  • Unable to decrease partition

    In 2012 I used bootcamp to get windows 7 on my macbook pro 8.1, running Lion. I was able to resize the partition at any time, over the last year windows 7 has become less needed and frankly it's a sucky OS anyway even compared to XP so I'm happy to r