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612
bio website google.com
location Geosynchronous orbiting HQ
age 94
visits member for 5 years, 1 month
seen Jul 11 at 8:50
Linux geek

Dec
29
comment What can cause kernel out_of_memory error?
He's using the RHEL5 kernel which has a lot of patches on top of vanilla 2.6.18, and gets security updates from the vendor. That being said, 2.6.18-164.9.1 is old and has several more or less serious vulnerabilities (newest EL5 kernel ATM being 2.6.18-194.26.1).
Nov
15
comment What is the function in Windows similar to Inode in Linux?
You mean the inode number of a file, or?
Nov
15
comment Accessing file on XFS partition over NFS locks up application
@pehrs: That's not the relevant choice, though. In reality, it's "lose data and don't get any indication which writes failed" vs. "wait until the server comes back online, or explicitly kill the app (with intr), or reboot the client"
Nov
15
comment Accessing file on XFS partition over NFS locks up application
@pehr: Yeah, well, soft mounts are quite convenient, at least until you lose data. ;-)
Nov
9
comment setting up a password for cron rsync over ssh
+1 ssh command keys or scponly/rssh is the correct approach.
Nov
1
comment Find out if the OS is running in a virtual environment
Duplicate of serverfault.com/questions/189447/…
Oct
29
comment What is the OSPM Power management feature in current HPC clusters?
@kashyapa: Most clusters run just the stock RHEL kernel. If that kernel supports the ACPI power management system of the hardware, sure, the ondemand governor can be used. But why would we? We run at full load 24/7/365, and there is the concern that switching into sleep states will cause jitter which is poison for tightly synchronized parallel applications.
Oct
26
comment Suggestions for recommended file system for Linux server
@Javier: I was specifically thinking about XFS spending quite a lot of IO BW on relogging in many metadata-intensive workloads. FWIW, as of 2.6.35 there is an experimental mount option for addressing this. See e.g. mjmwired.net/kernel/Documentation/filesystems/… . For a practical example, consider rm -rf linux-kernel-source-tree.
Oct
26
comment Suggestions for recommended file system for Linux server
For more anecdotal evidence, I've lost data with ext3, so it's not like it's invincible. So far, no data loss with ext4, although to be fair I've used it much less than ext3.
Oct
19
comment Need help debugging: Suspect file server is running slowly because of nfs load
Presumably your NFS server doesn't have a RAID controller with battery backed write cache? Ours has (well, it's a SAN array), and we run ~100 desktops with sync mounted homes with no problems.
Oct
10
comment Using 4k drives with md/LVM/dm-crypt
@Tom. Many filesystems use a 4 KB block size, so larger sectors would result in a lot of performance-sapping read-modify-writes. Secondly, the drive towards bigger sectors was primarily to increase the ECC efficiency, and there are diminishing returns for making it even bigger.
Sep
6
comment Ubuntu 10.04: disk check at boot takes a long time
Are you using ext3, ext4 or something else? FWIW fsck on ext4 is almost an order of magnitude faster than on ext3.
Sep
3
comment Linux stretch cluster: MD replication, DRBD or Veritas?
Since the OP mentioned "stretch cluster" rather than regular ha-clustering, seems he wants to protect against his SAN array going down as well, in which case he does need replication. That replication can of course be DIY with DRBD or similar, or some $$$ solution from the SAN array vendor.
Aug
4
comment How many subdirectories can a directory have on RH5 Linux?
That was actually "Rajat" and not the OP
Jun
24
comment Server was hacked. Now login wont accept 'root' as username comes up invalid
See picture at nukeitfromorbit.com
Jun
22
comment Server setup - Removing unnecessary Ubuntu 10.4 LTS packages
No, gcc (a C compiler) is most certainly not part of the kernel.
Jun
16
comment Networked filesystem with user level security for linux
@Konrads: Not if you use kerberos, as Mr. Brandt mentioned. Even if matt has root on his own workstation, he cannot get Joe's TGT.
May
20
comment Time sync in data center
@dbasnett: Yes, I know what stratum means. Which is why I wrote that in case one for some reason don't want to synchronize from some external NTP server(s), one can setup a stratum-0 source for internal use. The price for such a thing can vary from < $100 for a GPS receiver to, well, a lot for a high-precision atomic clock.
May
20
comment Linux: Why change inode size?
@FractalizeR. Yes, mke2fs on RHEL/CentOS 5 dates back to 2006. I think the default changed a few years ago, sometime when ext4 was declared stable maybe.
May
20
comment Time sync in data center
@dbasnett: No, I did not.