I am currently trying to install SAP servers on Linux and I've run into a bit of a situation. Script must follow below steps
Set swap size
Reboot server
Perform SAP installation.
So I have created the single script which will set the swap space & do the installation but not sure how I can add the reboot feature in it. I read some blogs which refers to use /etc/rc.local but it seems in this case I will have to create two scripts:
Script 1: It will set the value for swap space & then add the calling of second script in rc.local
Script 2: It will have syntax to perform SAP installation.
is there any way that I use single script to for complete setup??
You can use a swapfile, a reboot is not required:
# Create swapfile of 2G
dd if=/dev/zero of=/swapfile bs=1M count=2048
mkswap /swapfile
swapon /swapfile
# Run SAP installation
# If you don't need the additional swap after the installation ...
swapoff /swapfile # Might take a while
rm /swapfile
Related
I am using opensuse, specific the variant on mono's website when you click vmware
I get this error. Does anyone know how i might fix it?
make[4]: Entering directory `/home/rupert/Desktop/llvm/tools/clang/tools/driver'
llvm[4]: Linking Debug+Asserts executable clang
collect2: ld terminated with signal 9 [Killed]
make[4]: *** [/home/rupert/Desktop/llvm/Debug+Asserts/bin/clang] Error 1
The full text can be found here
Your virtual machine does not have enough memory to perform the linking phase. Linking is typical the most memory intensive part of a build since it's where all the object code comes together and is operated on as a whole.
If you can allocate more RAM to the VM then do that. Alternatively you could increase the amount of swap space. I am not that familiar with VMs but I imagine the virtual hard drive you set-up will have a swap partition. If you can make that bigger or allocate a second swap partition that would help.
Increasing the RAM, if only for the duration of your build, is the easiest thing to do though.
Also got the same issue and solved by doing following steps (It is memory issue only) -
Checks current swap space by running free command (It must be around 10GB.).
Checks the swap partition
sudo fdisk -l
/dev/hda8 none swap sw 0 0
Make swap space and enable it.
sudo swapoff -a
sudo /sbin/mkswap /dev/hda8
sudo swapon -a
If your swap disk size is not enough you would like to create swap file and use it.
Create swap file.
sudo fallocate -l 10g /mnt/10GB.swap
sudo chmod 600 /mnt/10GB.swap
OR
sudo dd if=/dev/zero of=/mnt/10GB.swap bs=1024 count=10485760
sudo chmod 600 /mnt/10GB.swap
Mount swap file.
sudo mkswap /mnt/10GB.swap
Enable swap file.
sudo swapon /mnt/10GB.swap
I tried with make -j1 and it works!. But it takes long time to build.
I had the same problem building on a VirtualBox system. FWIW I was building on a laptop with XP and 2GB RAM. I had to bump the virtual RAM up to 1462MB to get a successful build. Also note the recommended disk size of 8GB is not sufficient to build and install both LLVM and Clang under Ubuntu. I'd recommend at least 16GB.
I would suggest using of -l (--max-load) option instead of limiting -j in this case. Possibly helpful
answer.
I am creating a cluster of machines in AWS (Amazon Linux 2) using terraform by utilizing the user_data argument under the aws_instance resource. Part of the script is the creation of a swap partition. The commands in my script work perfectly if I execute them manually in the instance.
I have tried the following in my script. It creates the partition successfully, but it does not seem to finish up creating the swap as confirmed in more /proc/swaps. It successfully executes the lines of code below everything I have showed that I omitted from my post. So it must be failing at the partprobe, mkswap /dev/nvme1n1p2, or swapon /dev/nvme1n1p2. It runs the echo "/dev/nvme1n1p2 swap swap defaults 0 0" >> /etc/fstab. I'm not sure how to tell where it is not executing.
# Create SWAP partition
fdisk /dev/nvme1n1 <<EOF
n
p
2
+48G
w
EOF
partprobe
mkswap /dev/nvme1n1p2
swapon /dev/nvme1n1p2
echo "/dev/nvme1n1p2 swap swap defaults 0 0" >> /etc/fstab
The results intended are to create swap partition as confirmed by running more /proc/swaps. The partition is created, but not the actual swap.
UPDATE: Here is the contents of the log file:
mkswap: cannot open /dev/nvme1n1p2: No such file or directory
swapon: cannot open /dev/nvme1n1p2: No such file or directory
However that device is listed when running lsblk and the command works if I run it manually.
Solution from the comments by #thatotherguy:
I'm guessing it's a race condition with partprobe. If you run manually, there will be several seconds between each command so udev will have plenty of time to create device node asynchronously. When you run them in a script, it doesn't. You could try adding sleep 5 after partprobe.
This solved the OP's error, and I can also report success using this fix.
I am trying to increase swapfile size on my raspberry pi 3.
I'm following this guide here on DigitalOcean.
After successfully increasing the file and setting it up using mkswap and swpon commands everything works fine. I even tried filling my ram with random data to see if it is going to use the new swap space and it works perfectly.
However after I reboot my raspberry, swap file returns to the previous (default) size of 100MB.
Is there any way to make this change permanent?
I'm running Raspberry pi 3 on Raspbian Jessie.
I figured it out.
Modifying /etc/dphys-swapfile solves all problems.
I just changed CONF_SWAPSIZE=100 to CONF_SWAPSIZE=2000
dphys-swapfile is responsible for setting up, mounting/unmounting and deleting swap files.
In the configuration file you can also specify the location of the swap file as well as few other parameters.
Suppose you have got to the point where swapon -s returns
# sudo swapon -s
Filename Type Size Used Priority
/swapfile file 4194300 0 -1
Now to make this change permanent you need to add a record about your new swapfile in fstab.
You need to add the following line:
/swapfile none swap sw 0 0
The meaning of the fstab fields is as follows:
#1.source 2.mountpoint 3.fstype 4.options 5.freq 6.order
I have written a script which requires to read a few entries in /etc/fstab. I have tested the script by manually adding some entries in /etc/fstab and then restored the file to its original contents, also manually. Now I would like to automate those tests and run them as a seperate script. I do, however, not feel comfortable with the idea of changing /etc/fstab altered. I was thinking of making a backup copy of /etc/fstab, then altering it and finally restoring the original file after the tests are done. I would prefer it if I could temporarily alter the location of fstab.
Is there a way to alter the location of fstab to, say, /usr/local/etc/fstab so that when mount -a is run from within a script only the entries in /usr/local/etc/fstab are processed?
UPDATE:
I used bishop's solution by setting LIBMOUNT_FSTAB=/usr/local/etc/fstab. I have skimmed the man page of mount on several occasions in the past but I never noticed this variable. I am not sure if this variable has always been there and I simply overlooked it or if it had been added at some point. I am using mount from util-linux 2.27.1 and at least in this version LIBMOUNT_FSTAB is available and documented in the man-page. It is in the ENVIRONMENT section at the end. This will make my automated tests a lot safer in the future.
UPDATE2:
Since there has been some discussion whether this is an appropriate programming question or not, I have decided to write a small script which demonstrates the usage of LIBMOUNT_FSTAB.
#!/bin/bash
libmount=libmount_fstab
tmpdir="/tmp/test_${libmount}_folder" # temporary test folder
mntdir="$tmpdir/test_${libmount}_mountfolder" # mount folder for loop device
img="$tmpdir/loop.img" # dummy image for loop device
faketab="$tmpdir/alternate_fstab" # temporary, alternative fstab
# get first free loop device
loopdev=$(losetup -f)
# verify there is a free loop device
if [[ -z "$loopdev" ]];then
echo "Error: No free loop device" >&2
exit 1
fi
# check that loop device is not managed by default /etc/fstab
if grep "^$loopdev" /etc/fstab ;then
echo "Error: $loopdev already managed by /etc/fstab" >&2
exit 1
fi
# make temp folders
mkdir -p "$tmpdir"
mkdir -p "$mntdir"
# create temporary, alternative fstab
echo "$loopdev $mntdir ext2 errors=remount-ro 0 1" > "$faketab"
# create dummy image for loop device
dd if=/dev/zero of="$img" bs=1M count=5 &>/dev/null
# setup loop device with dummy image
losetup "$loopdev" "$img" &>/dev/null
# format loop device so it can be mounted
mke2fs "$loopdev" &>/dev/null
# alter location for fstab
export LIBMOUNT_FSTAB="$faketab"
# mount loop device by using alternative fstab
mount "$loopdev" &>/dev/null
# verify loop device was successfully mounted
if mount | grep "^$loopdev" &>/dev/null;then
echo "Successfully used alternative fstab: $faketab"
else
echo "Failed to use alternative fstab: $faketab"
fi
# clean up
umount "$loopdev" &>/dev/null
losetup -d "$loopdev"
rm -rf "$tmpdir"
exit 0
My script primarily manages external devices which are not attached most of the time. I use loop-devices to simulate external devices to test the functionality of my script. This saves a lot of time since I do not have to attach/reattach several physical devices. I think this proves that being able to use an alternative fstab is a very useful feature and allows for scripting safe test scenarios whenever parsing/altering of fstab is required. In fact, I have decided to partially rewrite my script so that it can also use an alternative fstab. Since most of the external devices are hardly ever attached to the system their corresponding entries are just cluttering up /etc/fstab.
Refactor your code that modifies fstab contents into a single function, then test that function correctly modifies the dummy fstab files you provide it. Then you can confidently use that function as part of your mount pipeline.
function change_fstab {
local fstab_path=${1:?Supply a path to the fstab file}
# ... etc
}
change_fstab /etc/fstab && mount ...
Alternatively, set LIBMOUNT_FSTAB per the libmount docs:
LIBMOUNT_FSTAB=/path/to/fake/fstab mount ...
I've seeing occasional segmentation faults in glibc on several different Fedora Core 9 Hudson Slaves. I've attempted to configure each slave to generate core files and place them in /corefiles, but have had no luck.
Here is what I've done on each linux slave:
1) Create a corefile storage location
sudo install -m 1777 -d /corefiles
2) Directed the corefiles to the storage location by adding the following to /etc/sysctl.conf
kernel.core_pattern = /corefiles/core.%e-PID:%p-%t-signal_%s-%h
3) Enabled unlimited corefiles for all users by adding the following to /etc/profile
ulimit -c unlimited
Is there some additional Linux magic required or do I need to do something to the Hudson slave or JVM?
Thanks for the help
Did you reboot or run "sysctl -p" (as root) after editing /etc/sysctl.conf ?
Also, if i remember correctly, ulimit values are per user and calling ulimit wont survive a boot. You should add this to /etc/security/limits.conf:
* soft core unlimited
Or call ulimit in the script that starts hudson if you don't wont everyone to produce coredumps.
I figured this out :-).
The issue is Hudson invokes the bash shell as a non-interactive shell, which will bypass the ulimit setting in /etc/profile. The solution is to add the BASH_ENV environmental variable tothe Hudson slaves and set the value to a file with ulimit -c unlimited set.