One John

We have several servers exposed to the internet.  Being Linux servers, we manage them by ssh.  For security, we only allow key access — no passwords.  But we still get a HUGE number of login attempts from — how shall I put it — unauthorized users.  We always had no passwords set (! in the shadow file, not blank) and root disallowed from ssh so nobody could have logged in, but they still tried.  Even after I turned off PasswordAuthentication, we still got attempts.
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My company recently got a Dell MD3000i “SAN” for a pretty good deal.  We’re starting to dabble in such things as virtualization, and the offer was too good to refuse.  The MD3000i is pretty basic.  Really it seems like just a JBOD with an iSCSI head, but it is a good way to start to play in that space.   We got it with dual controllers and about 6TB of space.
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Worst case: a new admin didn’t read my previous note correctly, and in order to “resolve” the block unmerged ss and com_err without first fetching the new packages.  What do you do now?  You can’t rsync the files over from another server, nor does scp work.  A co-worker of mine used -pv instead of -av on his –featchonly emerge and ran into this problem.  (more…)

Gentoo appears to have released a change before releasing the portage that can handle it. If you emerge world right now, you’ll probably get a block involving sys-fs/e2fsprogs, sys-libs/ss and sys-libs/com_err. You’ll see something like this:
[blocks B ] sys-libs/e2fsprogs-libs-1.41.0)
[blocks B ] sys-libs/ss (is blocking sys-libs/e2fsprogs-libs-1.41.0)
[blocks B ] sys-libs/com_err (is blocking sys-libs/e2fsprogs-libs-1.41.0)

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At work we upgraded some of our server a while ago and ran into a problem when upgrading from OpenSSH 4.5 to 4.6. It just stopped working. We use LDAP authentication and It would log an error “‘user’ is not in ‘sshgroup’”.

“id user” would confirm that they were indeed in sshgroup, and interestingly enough, adding them to a local group “sshgroup” would not help either.
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For a couple of years now, one of my Windows XP workstations has taken about 10 minutes to start responding on the network. The 10 minutes would be spent trying to start the Server service. Then an error 7022 with a message “The Server service hung on starting.” would be entered in the System Event Log, the Server service would be restarted, and everything would be fine. (more…)

I recently installed qmail (mail-mta/netqmail in Portage) on an Intel based server under x86_64 Gentoo. Everything seemed fine, but when qmail-smtpd tried to receive remote email, it would die with the following error:

2008-08-22 10:51:38.328444500 tcpserver: status: 1/40
2008-08-22 10:51:38 tcpserver: pid 5004 from 192.168.0.33
2008-08-22 10:51:38 tcpserver: ok 5004 franklin:192.168.0.4:25 newyork:192.168.0.33::4878
2008-08-22 10:51:38 /var/qmail/bin/qmail-smtpd: error while loading shared libraries: \
   libcom_err.so.2: failed to map segment from shared object: Cannot allocate memory
2008-08-22 10:51:38 tcpserver: end 5004 status 32512
2008-08-22 10:51:38 tcpserver: status: 0/40

Google didn’t show any association between libcom_err and qmail, but “failed to map segment” turned up other problems associated with softlimit.
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Just ran into this bug in FireFox: https://bugzilla.mozilla.org/show_bug.cgi?id=412112. Basically, if you do a synchronous call on an XMLHttpRequest object, the onreadystatechange function is not called. So the following code doesn’t work.

var request = new XMLHttpRequest();
request.onreadystatechange = function () {
if (request.readyState == 4)
  if (request.status == 200) alert('request successful')
};
request.open("GET", "/index.html", false); /* the false here makes it synchronous *
request.send(null);

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I just upgraded my Tivo to a Tivo HD (very cool) and lost the old tip on how to avoid recording 5 copies of The Daily Show every day. Apparently Comedy Central doesn’t provide enough metadata for the Tivo to figure out when an episode is new and when it is a rerun. This little trick was in a Tivo Newsletter:

WishList(r) Search Suggestion: De-dupe Your Now Playing List
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I was working on an interesting little project involving the Google Website Optimizer and ran into this little gem.

The task was to use JavaScript to rewrite a page that was formatted using tables and was sometimes missing a row that spanned the whole table. Now I have to admit that I am not a JS or DOM pro, But I’ve picked up though some experience through this and a couple other tasks. So here is the base HTML: (more…)