Thanks for the suggestions Adam. Sadly, removing the .jedit dir (or in my case ~/Library/jEdit/, since I'm on MacOS) did not resolve the problem, which at least gives us some more information, I guess. 

I've been comparing the problem key with one that works on another server, and the permissions are exactly the same, so I don't think it's a permissions issue, and I've used tcpdump to confirm that jEdit isn't even talking to the ssh server when it repeatedly prompts for my passphrase, so which proto versions are supported on the server don't enter into it (they should both be ssh 2 keys anyway). 

The only difference I can find is that the working key is shorter than the non-working one, but the non-working one is 2048 bits and I am almost certain that previous working keys were that long, and I'd be surprised if the plugin had a max key length. Still, if straws are all I have to grasp at... Alan (or someone else with dev knowledge of the plugin) can you confirm?

One suggestion that might be worth taking from this, for the devs: the passphrase rejections generate no log messaging whatsoever, either to the Activity Log or to stdout when I run jEdit from the command line. Whatever the issue turns out to be, some kind of diagnostic message when a passphrase is reject would be helpful. 

Thanks again to all who've tried to help. I remain open to any other troubleshooting suggestions. :(

--Brad


On Tue, Nov 20, 2012 at 4:02 AM, Adam T. Bowen <adamb@agitate.org.uk> wrote:
Hi Brad,

Have you tried temporarily moving your entire .jedit settings directory out of the way and setting up the connection from scratch? It would entirely rule out any sort of cached data or old settings issue if it still couldn't connect.

If it works, then you have to decide whether to spend time trying to sniff out the offending setting/cache file, or you can just set things up again from scratch. Whichever is less painful I suppose.

A couple of other thoughts:

* It could be a file permissions issue. What are the permissions on your .ssh directory and key files? Local and remote. I know you say it works from the command line, but it is a different client, and may have different file permission requirements.

* What SSH protocols does the server support? I presume the Java client used in the FTP plugin supports both versions 1 and 2 of the SSH protocol. Presumably so does your server, but worth checking.

Cheers,

Adam


On 19/11/12 18:43, Alan Ezust wrote:
According to the event log, the wrong passphrase is being entered, or
the dialog is being closed without a passphrase.
But it is using a key, that is apparent (although you sanitized the
paths so only you can know for sure if it is using the correct key!).
Anyway, I am unable to reproduce your problem now.

On Mon, Nov 19, 2012 at 10:30 AM, Brad Smith <usernamenumber@gmail.com
<mailto:usernamenumber@gmail.com>> wrote:

    Unfortunately I do not. Also, given that jEdit keeps prompting me
    for the passphrase and my reading of the event log, I don't think
    we're even reaching the point where the key is actually being used
    for authentication.

    Thanks for the response nonetheless,
    --Brad


    On Mon, Nov 19, 2012 at 10:40 AM, Colin Law <clanlaw@googlemail.com
    <mailto:clanlaw@googlemail.com>> wrote:

        On 19 November 2012 15:30, Brad Smith <usernamenumber@gmail.com
        <mailto:usernamenumber@gmail.com>> wrote:
         > Well I went and got my hopes up, but no luck so far. Any
        suggestions for
         > troubleshooting further? And yes, ssh-add + regular ssh from
        CLI works fine.
         >
         > Here's the activity log, slightly sanitized by replacing
        username, hostname,
         > and keyname, though I don't think it's going to be of much
        help. The big
         > Java error at the bottom is just me clicking Cancel after a
        failed attempt
         > to enter the key's passphrase.

        Have a look at the ssh log on the server if you have access to
        it, it
        may tell you something.

        Colin

         >
         > Thanks for the response, and for any help you can offer!
         >
         > --Brad
         >
         > 10:23:06 AM [AWT-EventQueue-0] [debug] FtpVFS:
         >
        FtpVFS.createVFSSession(sftp://USERNAME@MYHOSTNAME:22/u0/USERNAME,
         >
        org.gjt.sp.jedit.browser.BrowserView[,0,116,892x667,invalid,layout=java.awt.BorderLayout,alignmentX=0.0,alignmentY=0.0,border=javax.swing.border.EmptyBorder@5ee819a8,flags=9,maximumSize=,minimumSize=,preferredSize=])
         > 10:23:06 AM [AWT-EventQueue-0] [debug] String:
         > sftp://USERNAME@MYHOSTNAME:22/u0/USERNAME
         > 10:23:06 AM [jEdit Worker #2] [debug] ConnectionManager:
        Thread[jEdit Worker
         > #2,6,jEdit Workers]: Connecting to sftp://MYHOSTNAME:22
         > 10:23:06 AM [jEdit Worker #2] [debug] SFtpConnection:
         > info.privateKey=/Users/USERNAME/.ssh/PATH/TO/KEY
         > 10:23:06 AM [jEdit Worker #2] [debug] SFtpConnection: Using key:
         > /Users/USERNAME/.ssh/PATH/TO/KEY
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        Connecting to MYHOSTNAME
         > port 22
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        Connection established
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: Remote
        version string:
         > SSH-1.99-OpenSSH_5.3p1 Debian-3ubuntu7
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: Local
        version string:
         > SSH-2.0-JSCH-0.1.42
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: CheckCiphers:
         >
        aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,3des-ctr,arcfour,arcfour128,arcfour256
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_KEXINIT sent
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_KEXINIT received
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: kex:
        server->client
         > aes128-ctr hmac-md5 none
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: kex:
        client->server
         > aes128-ctr hmac-md5 none
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_KEXDH_INIT sent
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: expecting
         > SSH_MSG_KEXDH_REPLY
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        ssh_rsa_verify:
         > signature true
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: Host
        'MYHOSTNAME' is
         > known and mathces the RSA host key
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_NEWKEYS sent
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_NEWKEYS received
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_SERVICE_REQUEST
         > sent
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        SSH_MSG_SERVICE_ACCEPT
         > received
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger:
        Authentications that can
         > continue: publickey,keyboard-interactive,password
         > 10:23:06 AM [jEdit Worker #2] [message] SftpLogger: Next
        authentication
         > method: publickey
         > 10:23:06 AM [jEdit Worker #2] [debug] SFtpConnection:
        Passphrase for
         > /Users/USERNAME/.ssh/PATH/TO/KEY
         > 10:23:06 AM [jEdit Worker #2] [debug] SFtpConnection:
        Passphrase for
         > /Users/USERNAME/.ssh/PATH/TO/KEY
         > 10:23:11 AM [jEdit Worker #2] [debug] SFtpConnection:
        Passphrase for
         > /Users/USERNAME/.ssh/PATH/TO/KEY
         > 10:23:12 AM [AWT-EventQueue-0] [debug] EditBus:
         > DynamicMenuChanged[menu=recent-files,source=null]
         > 10:23:12 AM [AWT-EventQueue-0] [debug] EditBus:
         > DynamicMenuChanged[menu=recent-files,source=null]
         > 10:23:14 AM [jEdit Worker #2] [message] SftpLogger:
        Disconnecting from
         > MYHOSTNAME port 22
         > 10:23:14 AM [jEdit Worker #2] [debug] ConnectionManager: catch
         > java.io.IOException on sftp://MYHOSTNAME:22
         > 10:23:14 AM [jEdit Worker #2] [error] ListDirectoryBrowserTask:
         > java.io.IOException: com.jcraft.jsch.JSchException: Auth cancel
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > ftp.SFtpConnection.<init>(SFtpConnection.java:107)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > ftp.ConnectionManager.getConnection(ConnectionManager.java:317)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > ftp.FtpVFS.getConnection(FtpVFS.java:511)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > ftp.FtpVFS._listFiles(FtpVFS.java:222)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         >
        org.gjt.sp.jedit.browser.ListDirectoryBrowserTask._run(ListDirectoryBrowserTask.java:74)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > org.gjt.sp.util.Task.run(Task.java:64)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         >
        java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         >
        java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
         > 10:23:14 AM [jEdit Worker #2] [error]
        ListDirectoryBrowserTask:  at
         > java.lang.Thread.run(Thread.java:680)
         > 10:23:14 AM [jEdit Worker #2] [error] ErrorListDialog$ErrorEntry:
         > sftp://USERNAME@MYHOSTNAME:22/u0/USERNAME:
         > 10:23:14 AM [jEdit Worker #2] [error]
        ErrorListDialog$ErrorEntry: Cannot
         > list directory: java.io.IOException:
        com.jcraft.jsch.JSchException: Auth
         > cancel
         > 10:23:14 AM [jEdit Worker #2] [debug] ConnectionManager:
         > releaseConnection(null)
         >
         >
         > On Sun, Nov 18, 2012 at 9:46 PM, Alan Ezust
        <alan.ezust@gmail.com <mailto:alan.ezust@gmail.com>> wrote:
         >>
         >> I just released FTP 1.0.1 which fixed the issue I was
        having. I am not
         >> 100% sure if it is the same
         >> as yours. What platform is this? Can you use ssh-add or
        other ssh clients
         >> with the same key?
         >>
         >>
         >>
         >> On Sun, Nov 18, 2012 at 2:04 PM, Brad Smith
        <usernamenumber@gmail.com <mailto:usernamenumber@gmail.com>>

         >> wrote:
         >>>
         >>> jEdit 5.0pre1, FTP plugin v1.0.0. I looked around on the
        site and wiki
         >>> but couldn't find anything about an svn repo where I might
        get the latest
         >>> plugin, but if you point me to docs I'll upgrade and see if
        it helps.
         >>>
         >>> Thanks!
         >>> --Brad
         >>>
         >>>
         >>> On Sun, Nov 18, 2012 at 1:08 PM, Alan Ezust
        <alan.ezust@gmail.com <mailto:alan.ezust@gmail.com>> wrote:
         >>>>
         >>>> Using FTP plugin 1.0 and jEdit 5.1pre1, I can reproduce
        your issue.
         >>>> If I update to the version in SVN, FTP plugin 1.0.1, it
        seems to have
         >>>> been fixed already but nobody released it yet.
         >>>>
         >>>> What versions of jedit and FTP plugin are you using?
         >>>>
         >>>>
         >>>> On Fri, Nov 16, 2012 at 10:32 AM, Brad Smith
        <usernamenumber@gmail.com <mailto:usernamenumber@gmail.com>>

         >>>> wrote:
         >>>>>
         >>>>> Hi Folks,
         >>>>>
         >>>>> I recently updated the key I use to access one of my
        servers, and ever
         >>>>> since jEdit's FTP plugin has failed to unlock the key; it
        just keeps
         >>>>> prompting me to enter my passphrase as though I've been
        entering the wrong
         >>>>> one, though I'm certain I'm not. I have this nagging
        sense that I've
         >>>>> encountered and resolved this issue before, but for the
        life of me I can't
         >>>>> remember how. :(
         >>>>>
         >>>>> Here's a list of what I've tried so far:
         >>>>>
         >>>>> - Restarted jEdit
         >>>>>
         >>>>> - Told the plugin to clear all caches and passwords, and
        specified the
         >>>>> connection details from scratch (as opposed to using my
        old  bookmark)
         >>>>>
         >>>>> - Verified repeatedly that the same key/passphrase works
        for this
         >>>>> username/server from the command line
         >>>>>
         >>>>> - Confirmed that servers that use other keys still work
        with the FTP
         >>>>> plugin
         >>>>>
         >>>>> - Checked the Activity Log (nothing useful that I can see)
         >>>>>
         >>>>> - Just to check, removed the passphrase from my key.
        JEdit continues to
         >>>>> prompt for, and then reject, my passphrase!
         >>>>>
         >>>>> - ...BUT, according to the atimes on my keyfiles, jEdit
        is accessing
         >>>>> the correct key, and not the old one (none of the old
        passphrases work
         >>>>> anyway).
         >>>>>
         >>>>>
         >>>>> So... at this point I'm stuck. I would *really* like to
        stop using vim
         >>>>> over a slow ssh connection though, so any help would be
        greatly appreciated!
         >>>>>
         >>>>> Thanks!
         >>>>> --Brad
         >>>>>
         >>>>>
         >>>>>
        ------------------------------------------------------------------------------
         >>>>> Monitor your physical, virtual and cloud infrastructure
        from a single
         >>>>> web console. Get in-depth insight into apps, servers,
        databases,
         >>>>> vmware,
         >>>>> SAP, cloud infrastructure, etc. Download 30-day Free Trial.
         >>>>> Pricing starts from $795 for 25 servers or applications!
         >>>>> http://p.sf.net/sfu/zoho_dev2dev_nov
         >>>>> --
         >>>>> -----------------------------------------------
         >>>>> jEdit Users' List
         >>>>> jEdit-users@lists.sourceforge.net
        <mailto:jEdit-users@lists.sourceforge.net>

         >>>>> https://lists.sourceforge.net/lists/listinfo/jedit-users
         >>>>>
         >>>>
         >>>
         >>
         >
         >
         >
        ------------------------------------------------------------------------------
         > Monitor your physical, virtual and cloud infrastructure from
        a single
         > web console. Get in-depth insight into apps, servers,
        databases, vmware,
         > SAP, cloud infrastructure, etc. Download 30-day Free Trial.
         > Pricing starts from $795 for 25 servers or applications!
         > http://p.sf.net/sfu/zoho_dev2dev_nov
         > --
         > -----------------------------------------------
         > jEdit Users' List
         > jEdit-users@lists.sourceforge.net
        <mailto:jEdit-users@lists.sourceforge.net>

         > https://lists.sourceforge.net/lists/listinfo/jedit-users
         >

        ------------------------------------------------------------------------------
        Monitor your physical, virtual and cloud infrastructure from a
        single
        web console. Get in-depth insight into apps, servers, databases,
        vmware,
        SAP, cloud infrastructure, etc. Download 30-day Free Trial.
        Pricing starts from $795 for 25 servers or applications!
        http://p.sf.net/sfu/zoho_dev2dev_nov
        --
        -----------------------------------------------
        jEdit Users' List
        jEdit-users@lists.sourceforge.net
        <mailto:jEdit-users@lists.sourceforge.net>

        https://lists.sourceforge.net/lists/listinfo/jedit-users



    ------------------------------------------------------------------------------
    Monitor your physical, virtual and cloud infrastructure from a single
    web console. Get in-depth insight into apps, servers, databases, vmware,
    SAP, cloud infrastructure, etc. Download 30-day Free Trial.
    Pricing starts from $795 for 25 servers or applications!
    http://p.sf.net/sfu/zoho_dev2dev_nov
    --
    -----------------------------------------------
    jEdit Users' List
    jEdit-users@lists.sourceforge.net
    <mailto:jEdit-users@lists.sourceforge.net>

    https://lists.sourceforge.net/lists/listinfo/jedit-users




------------------------------------------------------------------------------
Monitor your physical, virtual and cloud infrastructure from a single
web console. Get in-depth insight into apps, servers, databases, vmware,
SAP, cloud infrastructure, etc. Download 30-day Free Trial.
Pricing starts from $795 for 25 servers or applications!
http://p.sf.net/sfu/zoho_dev2dev_nov