Archive for November, 2008
serious bug in xfs/lvm/raid10 ? no ideas…
I was trying to do some seriuos work, connected with migrating data to new server machine, which has four 73GB SCSI drives spinning up to 15000 rpm. The best performance for me should offer raid10, and as my test shown I was right. LVM over mdadm (software raid) device was a pretty good idea for better management of free space.
And so the story begun :)… as a result few days ago commited a bug in gentoo:
http://bugs.gentoo.org/show_bug.cgi?id=248674
it appears in PLD/centos too. I have no ideas of reason, or problem connected with this. Maybe you have some? Or you found sth like this:
raid10_make_request bug: can’t convert block across chunks or bigger than 256k
oneliner: copy file that has searched phrase
Because my server history sometimes changes, I have to write down my favourite oneliner - which copy every file from some which contains searched phrase/word.
for i in `egrep -li ’searched phrase’ *.eml`; do cp $i found/; done
if you just want to see those files, change cp to echo, like this
for i in `egrep -li ’searched phrase’ *.eml`; do echo $i; done
but this one - is made just by:
egrep -li ’searched phrase’ *.eml
minimize winamp to tray
Almost all day long I listen to ShoutCast radios, and winamp in system taskbar annoy me. I do not know why it does not apper in standard options (just like rightclick or sth), but there is an option to activate this
first - rightclick at winamp status bar and choose options-> preferences (or use hotkey ctrl+p)
then in general preferences find “Show winamp in: and instead of taskbar check system tray (as you can see at picture below)
and from now - it works, and it is not a “winamp agent”
thank you thinkpad :)
Few weeks ago, my thinkpad T61 hit the deck from about 1 meter (from my desk). It even doesn’t stop working, but there is some damages, you can see below. There was an occassion to make some photos inside (there will be better when I will recieve parts to change). I don’t believe that any other manufacturer can survive this situation better than my thinkpad.
one year
It is exacly one year after first post… one year of new challenges and experience. So… maybe some statistics.
My blog has 48195 visits (without bots)… and 33159 unique.
Thanks for all your comments (23), and to RSS readers (12).
Best regards for all,
And see you in the future :)… near I hope :]
convert security.fdb to security2.fdb in firebird
I have to migrate from firebird 1.5 to 2.0. And of course there was a databases migration. The security.fdb as it is said in /opt/firebird/upgrade/security_database.txt is not compatibile:
You can’t use pre-2.0 security database in firebird 2.0 or higher directly.
If you try to put old security.fdb into firebird’s new home directory with
new (security2.fdb) name, you will get a message - cannot attach to password
database. That’s OK and is by design. In order to be able to use old database,
you must run appropriate upgrade script - security_database.sql. To do so:
1. Put your old security database in some known to you place (not new home directory). Always have a copy of it!
2. Start firebird using it’s new, native security2.fdb.
3. Convert your old security database to ODS11 (i.e. backup and restore it using gbak from firebird 2.0). Without this step you will get failure running security_database.sql!
4. Connect to restored database as SYSDBA and run the script.
5. Stop firebird.
6. Copy upgraded database to firebird’s home directory (as security2.fdb).
7. Start firebird.
but point 3 is not explained. so… let’s rock…
To be sure - You have to change native sercurity2.fdb password to same as your sysdba in previous version of firebird has, and check if firebird is running!
# /opt/firebird/bin/changeDBAPassword.sh
Please enter current password for SYSDBA user: oldpassword
Please enter new password for SYSDBA user: masterkey
STEP 1 (make a copy of security.fdb):
# /opt/firebird/bin/gbak -user SYSDBA -password masterkey /opt/firebird/security.fdb /opt/firebird/security.fbk
if you get following error you have to chown security.fdb to firebird user!
gbak: ERROR:I/O error for file “/opt/firebird/security.fdb”
gbak: ERROR: Error while trying to open file
gbak: ERROR: Permission denied
gbak:Exiting before completion due to errors
STEP 2 (restore the database):
# /opt/firebird/bin/gbak -rep -user SYSDBA -password masterkey /opt/firebird/security.fbk /opt/firebird/security.fdb
STEP 3 (database conversion):
# /opt/firebird/bin/isql -user SYSDBA -password masterkey -i /opt/firebird/upgrade/security_database.sql /opt/firebird/security.fdb
STEP 4 (stop the firebird):
# service firebird stop:
STEP 5 (overwrite the old security fdb):
cp security.fdb security2.fdb
that’s all… simple don’t you think so?
WORN - Write Once Read Never - new trend in hard disk production?
Yesterday I participated Hitachi Storage training, which was about new AMS 2500 storage and its new active-active controller. A few white papers can be found below. I attach two additional links. One which has some interesting info about disk failures (from FAST’07: 5th USENIX Conference on File and Storage Technologies) and one about risk of raid5 in disks bigger than 750GB. So - remeber the WORN rule - which make SATA drives compleatly untrusted
symmetric-active-active-controller
transmission-1.40 at centos 5 libcurl problem
When I tried to update my transmission (1.34) bittorent client to newest version 1.40 at centos 5 I got a configure error:
Requested ‘libcurl >= 7.16.3′ but version of libcurl is 7.15.5
and it is true… libcurl in centos 5 is now 7.15.5 and probably will not be updated in a short time. As a solution, I tried to rebuild a fedora 8 src package.
What I need was: curl-7.16.4-8.fc8.src.rpm and rpmbuild in my centos system. You will probably need nss-devel and nspr-devel so install it before running rpmbuild. Let’s rock:
rpmbuild –rebuild –define ‘dist .el5′ curl-7.16.4-8.fc8.src.rpm
after some time you should get files:
-rw-r–r– 1 root root 675076 Nov 11 10:19 curl-7.16.4-8.el5.i386.rpm
-rw-r–r– 1 root root 206491 Nov 11 10:19 curl-devel-7.16.4-8.el5.i386.rpm
of course, you can download them from my repo (click at them). Now you can easly install both:
# rpm -Uvh /usr/src/redhat/RPMS/i386/curl-*
Preparing… ########################################### [100%]
1:curl ########################################### [ 50%]
2:curl-devel ########################################### [100%]
Duplicate name exists
After starting windows xp pro, I got:
Duplicate name exists.
Solution:
If changing name for sth random (for example 376huf2e) does not help, check if the workgroup name is not same as one of computers in your network. For me - it solved the problem.
software raid 10 at linux
Today I was looking for some performace tests at linux filesystems, and I found some pages, where raid 10 at linux has been done by merging two raid 1 into raid 0, or simmilar…
Maybe some of you does not know, that linux mdadm support raid10, as you can see below:
# mdadm –create /dev/md2 –level 10 –raid-devices=4 /dev/sda5 /dev/sdb5 /dev/sdc5 /dev/sdd5
mdadm: array /dev/md2 started.
and check:
# cat /proc/mdstat
Personalities : [raid1] [raid10]
md2 : active raid10 sdd5[3] sdc5[2] sdb5[1] sda5[0]
4481920 blocks 64K chunks 2 near-copies [4/4] [UUUU]
[======>..............] resync = 32.2% (1445184/4481920) finish=0.3min speed=160576K/sec