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18

Out of the box, you are guaranteed that iptables will start before the interface is brought up by the order of the startup scripts. Look at the "chkconfig" line in each startup script and you will see the runlevels it is "on" when active, the start order, and the stop order. You are not guaranteed that the interface will not be brought up if the iptables ...


15

You say in your comments that you're evaluating a netboot / network root environment. The first thing you must realize is there is no such thing as "vanilla" - you're not going to run CentOS 5.10 right out of the box with zero changes (if you think you are you're deluding yourself: NFS Root is already at least Strawberry, verging on Pistachio). If you want ...


9

You can boot using a Grub fallback entry. Add another stanza with either your new (or old) options, then choose the known-good as the fallback. Look into adding the panic=5 option as well (resets a system following kernel crash)


9

You can indeed use Grub to boot once only. You can also specify a fallback boot. Essentially, you use default saved at the start of your grub.conf, to indicate that you want to boot a saved entry by default. Then at the end of your experimental boot, use savedefault # to set the older boot options as the new saved value. So that every time you boot the ...


8

Install one system, boot it and check out the block layer statistics from /sys/block/${DEV}/stat e.g. /sys/block/sda/stat. Quoting from the documentation: The stat file consists of a single line of text containing 11 decimal values separated by whitespace. The fields are summarized in the following table, and described in more detail below: Name ...


7

I agree that your solution seems a bit complex, so I'll go with "give me some idea how this could be implemented in an entirely different way" :-) The standard solution for this is to use a configuration management system, such as puppet, and allow users to add their stuff to the puppet config for the server. Puppet will then push out the start script and ...


5

Reading regarding this on IBM support forums the suggestions to get it working are: Make sure you have latest Bios Ver. Make sure you have USB options selected in BIOS Insert USB and boot server Select F12 (Boot options) during boot up. USB will be displayed, select it and you will be prompted if you want to make it "Persistent" Boot. ...


4

A Dell PERC will be able to import the configuration from the disks as "Foreign Configuration". You should be able to access the controller's management interface and import the foreign configuration.


4

If you by Redhat mean the distribution, which was discontinued a decade ago, then it might be true, that it only supported initrd and not initramfs. But on newer distributions, the initrd names in /boot are just named like that for historical reasons. There was a period where distributions supported both. The kernel knew the difference and could tell the ...


4

It means your server isn't up. It could have failed at any step in the boot process. On bare-metal hardware, an EL6 server should take between 4 and 10 minutes to boot. It's possible that updates could have caused this issue. This could also be a hardware error. Ask your hosting company to get an IP KVM on the server and see what's on the screen at the ...


4

Has anyone seen this before on SuperMicro Super Servers? Yes, this just happened to me. Right before the screen turns blue there is an error message (I had to record it on my phone and play the video back to read it): error: Invalid mode: text I booted off a USB drive, mounted the file system and changed /etc/default/grub. Comment out the line: ...


4

You need, at minimum, After=network.target in the [Unit] section of your unit file, to ensure that the network is up before starting nginx. I have no idea why your unit file doesn't have it. Here is a complete example from my handy Fedora system, as shipped by Fedora: [Unit] Description=The nginx HTTP and reverse proxy server After=syslog.target ...


4

I used a fedora 20 iso and hosted it out to an entire lab. you don't mention what OS you're using, but check out PXEboot. It requires you have access to your DHCP server, a TFTP server, and storage enough to host your files. This method works for about every linux distro. I posted a howto a while back on my blog using fedora 20 as the client os and RHEL7 as ...


4

The main problem, that the bootloaders are a little bit complex today, and practically they need to be booted as well. Even this "bootloader booting code" is too big for the around 300 byte of code in the MBR (master boot record). This is because the boot loaders are using normally an extra data area, around 10-30 kbyte, after the master boot record. On ...


3

Since you just started, and haven't provided details other than "as told in the instruction", I'd start over. Sorry if that's not what you want to hear.


3

There must be some md metadata remaining on the sde device. Remove sde1 from the raid device. Wipe sde md metadata completely (using dd and depending on the version of metadata and their location on the disk) something like: dd if=/dev/zero of=/dev/sde bs=4096 count=1 seek=1 or even better: mdadm --misc --zero-superblock /dev/sde Re-create your sde1 ...


3

Something borked your winlogon.exe, probably a corrupt registry based on your details. Try boot to a last known good configuration. If that doesn't work, time to break out the backup and restore procedures.


3

Um... # The following is the partition information you requested # Disk Partioning clearpart --all --initlabel part /boot --size 64 --asprimary --ondrive=sda part pv.1 --size 286000 --ondrive=sda volgroup vg00 --pesize=65536 pv.1 The "part /boot --size 64" means exactly that. 64Mb /boot partition. Your problem lies with the automatic provisioning ...


3

You could use /etc/rc.local, it is present on all of the systems you mention. It is executed after all of the other initialisation scripts, see the comments in the file for more information.


3

I'm simply wondering if a Server 2012 Hyper-V VM can be sent over the network at startup through PXE boot. No, it cannot. For that matter, you can't do this with any other virtualization technology either. You simply can't "stream" an operating system over a network cable in the way you seem to be envisioning. can anyone suggest another method of ...


3

No, you should use your operating specific way of removing old versions of the Linux kernel. (yum for RHEL based like CentOS or Fedora, apt-get for Debian based like Ubuntu and so on)


2

I have a similar question, but its on this topic, so i figure I'll share my two cents and ask... First off, on a server it is highly feasible to have an iptables ruleset that changes frequently. I don't know who would think not. If you run port scan detection software, or other types of IPS (intrusion prevention software), these programs can be configured ...


2

I just installed Ubuntu 13.10 with a 105MB /boot. It installed fine, but after it rebooted I did the updater, it said that there was not enough space. Wanted around another 196MB for the upgrade, must be a kernel upgrade or something. So had to reinstall with a bigger /boot. Went for 500MB and that seemed to work. Good thing it doesn't take long to do a new ...


2

I haven't tried this before, and I'm not sure it's the best solution, but it should get you up and going... I'd strongly recommend you at least browse through the sources at the bottom to sanity check what I've got here... :) Basically, you'll need to boot off rescue media, rescan the PVs, VGs, and LVs. lvm pvscan lvm vgscan lvm lvscan Then, you ...


2

Using grub-install /dev/sdX is probably how it is intended to be done. However, I just had to rescue a CentOS 6.4 server that had that setup, but now froze at boot after its other bootable RAID 1 disk was replaced some months earlier (the server had stayed on during the meantime). What solved the issue in my case was grub-install /dev/md0, where md0 is the ...


2

You should try one of this (in case you have /dev/sda and /dev/sdb in your RAID 1): # grub-install /dev/sda # grub-install /dev/sdb OR # grub grub> root (hd0,0) grub> setup (hd0) grub> root (hd1,0) grub> setup (hd1) After this yo can try to load system with only one drive in test purposes.


2

My random guess would be power failure, or components failure. If its not a virtual environment, look into your ILO/DRAC/BIOS to get more log.


2

I want to know if there is some random I/O carried out by kernel processes that I'm unaware of? Well we don't know what you're aware of nor do you actually mention an operating system, but if we assume you mean Linux then there's unlikely to be anything purely-OS-based that would significantly benefit from the improved random IO capacity of an SSD ...


2

Initial configuration is usually done over the serial port. In theory you can do without it but debugging any problems is done blind - you can't see if it is set to use a static address or it is trying DHCP etc. NET MGT port: After the initial configuration of the system using the SER MGT port, communication with the SP and host is usually performed ...


2

When I had this problem with a *nix box (changed IP schemes, old IP was no longer valid) the only way I could get around hanging services at boot time was to start it in single-user mode and hand-modify the interfaces file (specifically /etc/sysconfig/network/network-scripts/ ..going from memory) then rebooting. You can boot into single user mode by ...



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