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Martin Hope
Martin C.
Asked: 2013-11-13 00:17:21 +0800 CST
  • 18

I have several PostgreSQL 9.2 installations where the timezone used by PostgreSQL is GMT, despite the entire system being "Europe/Vienna". I double-checked that postgresql.conf does not contain timezone setting, so according to the documentation it should fallback to the system's timezone.

However,

# su -s /bin/bash postgres -c "psql mydb"

mydb=# show timezone;
 TimeZone 
----------
 GMT
(1 row)

mydb=# select now();
              now              
-------------------------------
 2013-11-12 08:14:21.697622+00
(1 row)

Any hints, where the GMT timezone could come from? The system user does not have TZ set and the /etc/timezone and /etc/timeinfo seem to be configured correctly.

# cat /etc/timezone 
Europe/Vienna
# date
Tue Nov 12 09:15:42 CET 2013

Any hints are appreciated, thanks in advance!

postgresql
Martin Hope
Martin C.
Asked: 2009-10-08 07:29:19 +0800 CST
  • 0

I am using Xen hardware-based virtualization for sevaral Linux DomUs. One of them keeps failing randomly with I/O errors when there is heavy I/O load in other DomUs.

dmesg contains is the following

[885434.196928] sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT,SUGGEST_OK
[885434.196934] end_request: I/O error, dev sda, sector 1557062
[885434.246997] Aborting journal on device dm-1.
[885438.713821] __journal_remove_journal_head: freeing b_committed_data
[885438.728478] ext3_abort called.
[885438.728698] EXT3-fs error (device dm-1): ext3_journal_start_sb: Detected aborted journal
[885438.729192] Remounting filesystem read-only

And here a second output from a different incident:

[1532214.100163] sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT,SUGGEST_OK
[1532214.100169] end_request: I/O error, dev sda, sector 3751150
[1532214.100172] Buffer I/O error on device dm-1, logical block 275514
[1532214.100442] lost page write due to I/O error on dm-1
[1547950.515890] sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT,SUGGEST_OK
[1547950.515896] end_request: I/O error, dev sda, sector 5477734
[1547950.515900] Buffer I/O error on device dm-1, logical block 491337
[1547950.516358] lost page write due to I/O error on dm-1
[1547972.401281] Aborting journal on device dm-1.
[1547950.541130] ext3_abort called.
[1547950.541357] EXT3-fs error (device dm-1): ext3_journal_start_sb: Detected aborted journal
[1547950.541869] Remounting filesystem read-only
[1547950.542125] EXT3-fs error (device dm-1) in ext3_ordered_write_end: IO failure

Sectors do vary between crashes and I cannot find any erros if I check the disks (which are in an md1) from Dom0.

I experienced the same issues at work with VMWare ESX based virtualization before installing the VMWare tools, so I expect a driver issue, since there are no "Xen Tools" (like the VMWare tools) containing special drivers, I don't know how to fix the issue.

The DomUs are using Linux 2.6.24-24-server #1 SMP Tue Aug 18 16:51:43 UTC 2009 x86_64 GNU/Linux, and are based on Ubuntu 8.04.3 LTS (hardy), whereas the hypervisor and the Dom0 are Linux 2.6.26-2-xen-amd64 #1 SMP Fri Aug 14 10:19:53 UTC 2009 x86_64 GNU/Linux on Debian Lenny.

Anybody got any ideas on how to proceed?

linux
Martin Hope
Martin C.
Asked: 2009-07-11 15:07:32 +0800 CST
  • 2

Xen (like other) virtual machines allows VMs to be saved and resumed. Xen on Debian Lenny, for instance, is configured to save and resume virtual machines on Dom0 restarts.

Is it possible to have this behavior enabled, but prevent certain VMs from being saved? Reason behind this is that I have some VMs with client data that are using cryptsetup-luks to store the data encrypted and I'd rather not have the encryption key being paged out to the memory save file.

Or is encrypting the storage area of the memory save files the only way around this situation?

xen security
Martin Hope
Martin C.
Asked: 2009-07-11 12:20:18 +0800 CST
  • 0

I am currently trying to install Ubuntu 9.04 server as DomU using hardware virtualization. Whenever I boot up the domain, the splash screen works well, but as soon as I select "Install Ubuntu server", the domain keeps hanging with 100% CPU utilization indefinitly.

About 50% of the time, the following message is shown, the other 50% of the time, no message is shown at all:

ACPI: DMI BIOS year==0, assuming ACPI-capable machine

I tried various settings of acpi=0, acpi=1 in the domain's config file, I tried specifying acpi=off as kernel argument, I also tried acpi=force.

I am now run out of ideas, why the kernel won't boot. Neither "Install Ubuntu server" nor "Check disk for errors" will work, but Memtest86 works fine from the ISO.

Anybody got a hint how to proceed. I have to confess that I am quite new to Xen.

Edit: added, that it is for the server version.

I tried upgrading from previous installs as well. I could install 8.04 LTS and upgrade to 8.10, but after an upgrade to 9.04 the kernel hangs again. I suppose it "simply" is a kernel issue of 9.04.

virtualization xen ubuntu