I have a server with SATA- Hot Swap disks. I can do this, and swap out a disk, and re-partition
the new one, however the running Linux kernel hangs on to the old partition table in memory.
So even though the disk is not in use, and has been re-partitioned, I still need to reboot to
get the kernel to see the new partitions, and use them. Is there any way around this?
How to force kernel to re-read disk partitions on non-system disks?
I just restarted the Apache Server, because my server was using 4GB out of physical memory and 1.5GB out of 2GB swap memory.
This is happening while Apache is only processing 3 requests per second and the server specifications are huge overkill. Dual Xeon E5420 SuperMicro Barebone with 4GB DDR2 ECC fully buffered Memory.
I have problems finding the reasons to the leak. I have restarted the apache server so I cannot provide top and server-status information, until the next memory problems.
I have seen 50 httpd pid's in top (could be more) with 250mb per process. Pretty huge. While that specific pid in /server-status was only serving e.g. a 1kg image.
Code:
#
# Timeout: The number of seconds before receives and sends time out.
#
Timeout 120
#
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
#
KeepAlive Off
#
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
#
MaxKeepAliveRequests 100
#
# KeepAliveTimeout: Number of seconds to wait for the next request from the
# same client on the same connection.
#
KeepAliveTimeout 15
##
## Server-Pool Size Regulation (MPM specific)
##
# prefork MPM
# StartServers: number of server processes to start
# MinSpareServers: minimum number of server processes which are kept spare
# MaxSpareServers: maximum number of server processes which are kept spare
# ServerLimit: maximum value for MaxClients for the lifetime of the server
# MaxClients: maximum number of server processes allowed to start
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule prefork.c>
StartServers 24
MinSpareServers 5
MaxSpareServers 100
ServerLimit 256
MaxClients 256
MaxRequestsPerChild 4000
</IfModule>
# worker MPM
# StartServers: initial number of server processes to start
# MaxClients: maximum number of simultaneous client connections
# MinSpareThreads: minimum number of worker threads which are kept spare
# MaxSpareThreads: maximum number of worker threads which are kept spare
# ThreadsPerChild: constant number of worker threads in each server process
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule worker.c>
StartServers 8
MaxClients 1500
MinSpareThreads 125
MaxSpareThreads 750
ThreadsPerChild 25
MaxRequestsPerChild 0
</IfModule>
I would like to hear which configuration you think will be better for a hosting server.
I have allready a raid controller in the server.
I am more concerned with security.
Currently we're using HP servers with 4 hot-swap bays that hold 3.5" Seagate Cheetah 15K RPM SAS disks, which we can get in 300, 450, and 600 GB flavors.
I'm looking at the HP DL380/385 models which use 2.5" SAS disks. About the only decent 15K RPM SAS disk I've found in 2.5" form is the Seagate Savvio, but it doesn't come any larger than 146 GB.
Anyone know of another enterprise-class SAS disk that has all of the following attributes: 2.5", 15K RPM, SAS, and at least 300 GB?
(Please, no 10K RPM or SATA recommendations like the WD Velociraptor. I won't consider anything that's not 15K RPM SAS.)
I do not have a restore disk for my Toshiba laptop and there is a virus on it. Can I use my restore disk from my HP computer? Both use windows XP?
View 4 Replies View RelatedHardisk brands all had their ups and downs over time. So almost all brands made sometime bad drive models that failed (yes, even IBM)
I just finished reading an article that currently for servers it seems Seagate is the best (currently).
Some say Western, some say Maxtor, I heard everything. It seems nobody agrees or there isnt one that actually has the lowest failure rates.
It would be nice to hear from real experience on servers scenarios (not office, or desktop). The article also said Hitachi was one of the worst and my eyes just popped out. I found reviews of people here that said Hitachi where the bests. So to conclude it seems everybody has their own preference.
It would be nice to hear some Datacenters or people with tons of servers. I suppose recovery centers and datacenters probably have the best stats on which disks are failing the most.
How do you handle your mega space requirements for your high-use databases? Do any of you work with storage in the terabytes? If so, what kind of hardware and setup do you use?
Do you just have many commodity servers with maybe 100GB or so in each, or do you have some kind of shared RAID array set up? Or some kind of SAN?
Keep in mind I'm not talking about network storage (i.e. slow, personal use, file server) but rather high-speed intensive high-read/high-write database requirements.
What are the options for implementing such a solution?
What types of products fit such requirements? Could you comment on what things to look for when purchasing such a set of products?
I colo a 1U machine with 2-36gig drives. They're not in RAID, and I have it set to rsync backups to a remote machine on a regular schedule. I have another remote machine functioning as a secondary DNS. Neither of these 2 are on a large upstream pipe. I just bought 2-147gig drives that I'd like to replace the 36g's with. How does this sound for a scenario to accomplish this with little downtime (pre-pardon my noob'ish ways):
1. Do a complete rsync of the filesystem to my remote machine as well as sync the mysql db's (to 1 remote drive).
2. Pop that single rsync'd drive into an external enclosure.
3. Travel to datacenter, once there, plug external drive into laptop and start up a VM that boots off of that drive.
4. Sync again so external drive has the most up-to-date data.
5. Change over IP's from colo to VM on laptop.
6. Shutdown and swap out drives in colo'd box with the new ones.
7. Setup new drives as RAID 1, install OS, then rsync filesystem over from laptop to new drives in colo'd box.
8. Change back IP's.
What am I missing, or is there an easier way without a 2nd colo/dedicated server? Currently, the colo'd machine is using about 1.3Mbit/sec outbound and it's running a low load.
anyone know any managed dedicated server provider who we can mail our hard disks to? We have a small pipe to the Internet and this is the only avenue we've thought of.
Or perhaps another solution that we haven't thought of?
Up to now we've been using CentOS with SCSI/SATA disk shich weren't "hot swap", and now we're upgrading to a Dell PowerEdge 1950 revision III with SAS hot swap disks on a PERC RAID 6i (new model of raid controller from Dell).
OF COURSE, Dell ONLY supports Windows (and Red Hat at the very most on the Linux world) so we were told by a Microsoft Tech that to be able to extract a disk and replace with another it had to be done via software. (The software powers the disk down and then you replace it)
Does anyone use CentOS with hot swap SAS disks? Do you use any special software to monitor the disks and/or replace them?
For building a house for, ie, 30 VPS, what kind of disks are you using? normal SATA? Raptor? SCSI?
I am going to use Quad-core CPU with 4-8GB RAM, but still wondering about the disks
We're about to buy a Dell Poweredge 1950 with hot swap disks in a raid 1 configuration (might even think about other raid combinations).
We will be installing Centos 5 (never tried it - normally use Centos 4) + control panel
The question is: what happens when a disk fails? How do we find out?(Apart from looking at the server) Any software notices?
Once noticed, what is the standard procedure to replace the disk? (Remember they are "hot swap") Do you just pull one out and replace it? Surely you have to rebuild the array...
I have a server with 2 hard drives, say drive A and drive B. Right now all my files, database and data is on drive A, and drive B is empty. Since I have another drive available, I want to split the load between the two drives. I'm ok with having the web pages and the database on one drive. I mostly want to just have the data (I have about 500GB of data) split between the two drives. Note that I want to avoid duplicating the data. I want to have each file on either drive A XOR drive B.
Should I map a separate subdomain to drive B and then use that subdomain to serve the half of the data thats there? Is there something I can do with hard/soft links on the server so that even though the data is on 2 drives, users still use the same url to access data on either drive? Any other options?
if I order a RAID from a host, can I be confident that they're not going to put two of the same make, model and order in there?
Or at least run one of the disks for a significant time before using inserting into the RAID?
Since purchasing 16-disk arrray NAS server 4-5 months ago, 5 disks have crashed so far. They are all WD4000YS. They're all "Raid Edition" which supposed to last longer than typical drives. It has been puzzling me until now.
It turns out that "Data Lifeguard" feature was confusing the RAID controller to believe that the disk was dead, hence the "failed" disk. AFAIK, Western Digital released firmware update on 01/09/07 that's supposed to fix this.
[url]p_faqid=1493&p_created=1168299631&p_sid=vfEX7qri&p_accessibility=0&p_redirect=&p_lva=&p_sp=cF9zcmNoPTEmcF9zb3J0X2J5PSZwX2dyaWRzb3J0PSZwX3J vd19jbnQ9MiZwX3Byb2RzPTAmcF9jYXRzPTAmcF9wdj0mcF9jdj0mcF9zZWFyY2hfdHlwZT1hbnN3ZXJzLnNlYXJjaF9mbmwmcF9wYWdlPTEmcF9zZWFyY2hfdGV4dD1XRDQwMDBZUw**&p_li=&p_ topview=1
So, if you have WDxxxxYS on your pre-production server, pull them out for a firmware update first!
For me, I can only swap "hot-spare" out for a firmware update. For other disks, I'll just have to wait for them to "drop" out of the array first. I cannot take this server offline at all. Any suggestions?
If you want a quick run down as to WHY I want to do this, read here
Basically, my ISP could not get my server running stable on a simple raid 1 (or raid 5) so what it came down to was having them install my system on a single disk. I don't exactly like this, main reason being, if the system (or HDD) crashes, I'll end up with another several hours of down time... So here is my proposal:
Please Note: This will have to be accomplished on a live System (full backups!) over ssh as I don't trust my ISP to do things right as described in my post above.
Current Setup:
CentOS 5.3 x86_64
Dual Xeon 5410
16GB RAM
4x 750GB HDDs
/boot - /dev/sda1 - 512MB (real 471MB) ext3
/ - /dev/sda2 - 50GB (real 46GB) ext3
/home - /dev/sda3 - remaining space (real 642GB) ext3
swap - /dev/sdb1 - 32GB
/backup - /dev/sdb2 - remaining space (real 659GB) ext3
/dev/md0 - /dev/sdc + /dev/sdd - raid 1 (NOTE: uses entire disk, no partitions!)
Proposed Solution:
Code:
vgcreate -s 64M vg0 /dev/md0
lvcreate -L 512M -n lvboot vg0
lvcreate -L 50G -n lvroot vg0
lvcreate -L 5G -n lvtmp vg0
lvcreate --extent 100%FREE -n lvhome vg0
mkfs -t ext3 -m 1 /dev/vg0/lvboot
mkfs -t ext3 -m 1 /dev/vg0/lvroot
mkfs -t ext3 -m 1 /dev/vg0/lvtmp
mkfs -t ext3 -m 1 /dev/vg0/lvhome
Now, I'd like to 'init 1' at this stage but I can't, so I won't (possible solutions?? Possible to umount the / partition??)
Assuming I'd have to do this on a fully live system, I'd disable all services that I can
Code:
/etc/init.d/sendmail stop
/etc/init.d/postfix stop
/etc/init.d/saslauthd stop
/etc/init.d/httpd stop
/etc/init.d/mysql stop
/etc/init.d/courier-authlib stop
/etc/init.d/courier-imap stop
/etc/init.d/amavisd stop
/etc/init.d/clamd stop
/etc/init.d/pure-ftpd stop
/etc/init.d/fail2ban stop
/etc/init.d/syslogd stop
Then we copy all of our data from the single partitions to the raid disks
Code:
mkdir /mnt/newroot
mkdir /mnt/newroot/boot
mkdir /mnt/newroot/tmp
mkdir /mnt/newroot/home
Code:
mount /dev/vg0/lvboot /mnt/newroot/boot
mount /dev/vg0/lvroot /mnt/newroot/root
mount /dev/vg0/lvtmp /mnt/newroot/tmp
mount /dev/vg0/lvhome /mnt/newroot/home
(I think I covered everything)
Code:
umount -l /dev/sda1 (/boot)
umount -l /dev/sda3 (/home)
cp -dpRx /* /mnt/newroot/
mount /dev/sda1 /boot
cp -dpRx /boot/* /mnt/newroot/boot/
mount /dev/sda3 /home
cp -dpRx /home/* /mnt/newroot/home/
Once we have everything copied, update /etc/fstab and /etc/mtab to reflect the changes we made:
vi /etc/fstab
Code:
LABEL=/home /home ext3 defaults 0 3
LABEL=/ / ext3 defaults,usrquota,grpquota 1 1
LABEL=/boot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
LABEL=SWAP-sdb1 swap swap defaults 0 0
To
Code:
/dev/vg0/lvhome /home ext3 defaults 0 3
/dev/vg0/lvroot / ext3 defaults,usrquota,grpquota 1 1
/dev/vg0/lvboot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
LABEL=SWAP-sdb1 swap swap defaults 0 0
Moving on, we make a fail safe in the event this doesn't work out:
vi /boot/grub/menu.lst
find
Code:
default=0
add after
Code:
fallback=1
Then we find (in the same file):
Code:
title CentOS (2.6.18-164.el5)
root (hd1,0)
kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/vg0/vgroot
initrd /initrd-2.6.18-164.el5.img
Add before:
Code:
title CentOS (2.6.18-164.el5)
root (hd3,0)
kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/sda2
initrd /initrd-2.6.18-164.el5.img
Where (hd3,0) is /dev/sdc. If the system fails to boot to the raid then it'll auto boot to the single disk (/dev/sda)
then update my ramdisk:
mv /boot/initrd-`uname -r`.img /boot/initrd-`uname -r`.img_bak
mkinitrd /boot/initrd-`uname -r`.img `uname -r`
And now to set up grub...
Code:
grub
> root (hd0,0)
> setup (hd0)
we should see something like this:
Checking if "/boot/grub/stage1" exists... no
Checking if "/grub/stage1" exists... yes
Checking if "/grub/stage2" exists... yes
Checking if "/grub/e2fs_stage1_5" exists... yes
Running "embed /grub/e2fs_stage1_5 (hd0)"... 15 sectors are embedded.
succeeded
Running "install /grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.
Code:
> root (hd3,0)
> setup (hd3)
Again, we should see something like this:
Checking if "/boot/grub/stage1" exists... no
Checking if "/grub/stage1" exists... yes
Checking if "/grub/stage2" exists... yes
Checking if "/grub/e2fs_stage1_5" exists... yes
Running "embed /grub/e2fs_stage1_5 (hd1)"... 15 sectors are embedded.
succeeded
Running "install /grub/stage1 (hd1) (hd1)1+15 p (hd1,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.
Code:
> quit
From here I think we're ready to reboot, can't see where I missed anything. If all goes well then I should see my volume groups listed in 'df- h'
Due to data center limitations, I am restricted to 100GB on my primary disk but can have up to 2TB on a second disk.Is it possible to have the backup node use the second disk instead of the primary disk?Also is it possible to have multiple to have multiple backup nodes?
View 3 Replies View Relatedjust out of interest, does anyone know a ssh command(s) to bring up your servers hardware stats? Cpu type and clock speed, memory, disks etc.
I've looked everywhere for a shell command to show cpu type with no luck.
I am trying to install Magento on my apache server. I am running into the dreaded mcrypt issue as Magento needs it to run. I have now been googling for the past few hours and have gotten nowhere.
Here are my details:
Linux
Centos 5.5
PHP 5.3.3
x86_64
Plesk 12
I have tried installing all sorts of different repos and it just isn't working.
When I try to install using # yum install php-mcrypt I get the following:
Loaded plugins: fastestmirror
Package php-mysql is obsoleted by php-mysqlnd, trying to install php-mysqlnd-5.5.13-3.el5.remi.x86_64 instead
--> Processing Dependency: php53-gd for package: psa-php53-configurator
--> Processing Dependency: php53-imap for package: psa-php53-configurator
[Code].....
Does Parallels support Plesk 12 being installed on a Linux VM that is provisioned on Microsoft Windows Server 2012 R2 Hyper-V?Is it fully supported?
View 2 Replies View RelatedI am looking to start offering web hosting packages and I was wondering if it was worth offering just Linux hosting or Windows as well?
View 12 Replies View RelatedI need a powerfull vps with lxadmin control panel.
With support 24/7/365 and best uptime.
With 384 MB Ram.
Most if not all the applications that we produce use PHP/MySQL and we're currently on Windows/IIS environment.
We're looking to change our hosting company and upgrade our servers and I'm eager to migrate over Linux/Apache.
The only problem is, some of our applications use the COM object to integrate with PowerPoint, can this still be done on Linux.
Also is anybody aware of any other potential floors when migrating over?
i am a wap develper(mobile web).I need a vps with 30-40 Gigs of space and about 200-250 Bandwidth with cpanel.my bugget is under $35 .Please suggest me one for these requirements.
View 4 Replies View RelatedI tried going from swf to mpg by using
[url]
and I was thinking of going from mpg to avi using ffmpeg. The problem is that swf to mpg ran up with an error. I was wondering if anyone know of the best way to proceed with this.
There is also audio on the swf files.
I am looking at linux vps due to money constraints. Ive had lots of experience with windows vps... its really simple, just use remote desktop .
Is there something similar for linux vps? Giving me a desktop like environment to mess around in? How does that work? Is there a tutorial on how to use one, transfer files, etc.
im talking about using windows XP to community to a linux vps.
To make ASP run under Linux, PHP script files are saved as ASP extensions and are redirected to the PHP interpreter. So it looks like the server serves ASP files, but these are actually PHP scripts.
View 3 Replies View RelatedCan anyone recommend a decent VPS place, need atleast decent ram for apache, mysql, xcache, php, 200 - 400 BW, for hosting about 2 websites. (need them on a separate machine from my others). Good connectivity matters since our users will be mainly from all over euorpe, USA and Russia and former Russian region.
View 12 Replies View RelatedThere is some version of ASP.NET for linux that is reliable?
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