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Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.

I'm working on a Laravel project and I'm attempting to "add" and "commit" a number of files simultaneously and I've run into something I've never seen before.

Rather than plow ahead with solutions that seem intuitive on the web, I wanted to run this by some folks who I'm sure have seen this.

When I go to do a

"git commit -m "my message"

I get this error:

[code]error: invalid object 100644 6a247fefd088bae6baae483aa27872517393f5fe for 'app/Http/Controllers/Auth/ForgotPasswordController.php'
error: invalid object 100644 6a247fefd088bae6baae483aa27872517393f5fe for 'app/Http/Controllers/Auth/ForgotPasswordController.php'
error: Error building trees[/code\

When I went out to Google in an attempt to remedy the situation, I saw this:

https://medium.com/@panjeh/git-error-invalid-object-error-building-trees-44b582769457 (see also https://git-scm.com/book/en/v2/Git-Internals-Git-Objects)

Sha-1 looks as though it's just a way of telling GIT to overlook what would otherwise be a snag. Is that right?

Then I found this: https://stackoverflow.com/questions/17628305/windows-git-warning-lf-will-be-replaced-by-crlf-is-that-warning-tail-backwar

From what I can gather, depending on your OS, Windows is going to interpret LF differently than a Linux system, hence GIT looks at LF and wants to replace it with CRLF.


I'm getting to share this with another developer and I want to make sure that I'm not just blowing through something I need to be …
Hi Experts

we have ERP system SAP running on red hat Linux 7  using oracle 12C

from time to time our file system which reserved for ora logs  get full so fast out of the sudden

we are not able to know the root cause which  

process or transaction or user  generate such amount of logs

do you know anyway or tool to know such info

Jpg file does exist in "/var/www/pict" path, but html file below is not able to show Jpg file. Why?

        <!--div align="center"-->
        <div class="container" style="background:url('../pict/ID-10028343.jpg') no-repeat center top; Height:780px; Width:1220px; background-size:100% 100%; margin:0 auto; ">

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I am wondering how can we monitor the permission on char file using monit application

I have below char file


and below monitrc config

check file dev_null with path /dev/null
if failed permission 666 then exec "chmod 666 /dev/null" as uid root and gid wheel

But it doesn't seems to work when file /dev/null has permission 600

I really appreciate any help on that.
Dear All,

In the past few weeks, I noticed the mailcleaner gateway was being targeted with bruteforce and spam attacks from Russia and Iran, I deployed country block plugin on my firewall and blocked entire CIDR for both Russia and Iran and kept an eye on Mailcleaner for any attacks with authentication attempts.

Since then, I noticed the mailcleaner disk has went up from 25% to 76% with the path /var/mailcleaner/spam/ and all domains included full of spam files with size up to 35 GB.

I have few questions to clean some space and prior to that also.

Are those spam files ?
Are they released or not?
Is it safe to delete them?

Thank you
nextcloud issue:
i try to move ownership from one to other user:
both users has logged in to web access
i do the following from command line
sudo -u www-data php occ files:transfer-ownership "source-user" "destination-user

The target user is not ready to accept files. The user has at least to be logged in once.

What is wrong here?
I added a disk to RedHat 7 on Azure. After re-boot server, I cannot ssh to the server .
The following is the steps I did referring https://docs.microsoft.com/ja-jp/azure/virtual-machines/linux/attach-disk-portal .
Could you help me to resolve this issue?

1. I created a disk on Azure Portal.

2. Confirmed file types of existing disks.
[servername]$ df -T
Filesystem     Type     1K-blocks     Used Available Use% Mounted on
devtmpfs       devtmpfs    970560        0    970560   0% /dev
tmpfs          tmpfs       980972        4    980968   1% /dev/shm
tmpfs          tmpfs       980972    37856    943116   4% /run
tmpfs          tmpfs       980972        0    980972   0% /sys/fs/cgroup
/dev/sda2      xfs       30929148 30877300     51848 100% /
/dev/sda1      xfs         508580   116672    391908  23% /boot
/dev/sdb1      ext4       4061824    16380   3819400   1% /mnt/resource
tmpfs          tmpfs       196196        0    196196   0% /run/user/1008
tmpfs          tmpfs       196196        0    196196   0% /run/user/995

3. Confirmd a disk added by dmeg. sdc was added.
[servername]$ dmesg | grep SCSI
[    0.374123] SCSI subsystem initialized
[    1.075264] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 248)
[    3.073908] sd 3:0:1:0: [sdb] Attached SCSI disk
[    3.078645] sd 2:0:0:0: [sda] Attached SCSI disk
[12159.133527] sd 5:0:0:0: [sdc] Attached SCSI disk

4. Executed fdisk
[servername]$ sudo fdisk …
I have an ESXi Server in which I have a VM that I would like to utilize a USB device from a remote location from the server although it is still on the same LAN.

I have read that there are USB over IP devices available that would achieve what I am after. Can someone make a recommendation.

The VM is running linux and there is a possibility I could run it in docker as well. Is this still possible with Docker?
No DNS and trying to deploy a vCenter appliance with a reverse lookup requirement.

Anyone know how to create a reverse lookup without DNS to sorta trick the vCenter appliance to install? I believe the requirement is on the vCenter side and not the windows machine I'm using for the upgrade but if that's the case, I'd need a reverse for windows. I don't think I can do this with the hosts file but I don't know.

Thanks in advance
Assume you have a directory and you share this with group or user/s.
is it possible to create a folder in this directory and change only sharing for this folder to hide from group?
linke L/Unix permission start directory has permission 777 and som folder in this directory has 700 or 770, ... like that
Where is NTP configuration held on a Linux server?  For example, you can can find NTP info from Windows in the registry at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters.  Any help with this is greatly appreciated!
I remotely connect to virtual Linux box as follows:  From my windows 10 computer, I invoke WinSCP.  From WinSCP, I open puTTy terminal.  
Then, I can clone source code from servers such as GitLab and GitHub.

What protocol am I using to connect to GitLab.  Is it SSH?

From puTTy terminal, I entered following command to see if existing ssh keys are present:

$  ls -al ~/.ssh

existing ssh keys
I can connect to GitLab and clone source code but there are no ssh keys in my home directory?  How is it possible to connect to remote servers without ssh keys?
Hi there,

We have a cron job on an Oracle Linux 7 server that should run at 10PM CST every night, but some odd reason, it runs at 3PM MST.  We have checked the cron job details and it does say 21:00, for 9PM.  When I run "date", I get a time that shows CST as the timezone, but the cron job doesn't seem to be checking this.  Anything I should check/configure?

- Christian
In Linux I am getting this message:

Package 'linux-modules-extra-5.3.0-28-generic' is not installed, so not removed
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
 linux-image-generic-hwe-18.04 : Depends: linux-modules-extra-5.3.0-28-generic but it is not going to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).

How can I correct this?
Whats the best way to encrypt partitions in Ubuntu 16.04 after the OS is installed>?
I need help to establish a VPN connection from my home Linux box (Debian 10) to office's SonicWall TZ300 using strongswan ipsec.
Here is my config files:/etc/ipsec.conf
conn GroupVPN


# aggressive=yes disabled by default when auth by PSK. It's enabled by setting
# charon.i_dont_care_about_security_and_use_aggressive_mode_psk=yes in strongswan.conf
# see https://wiki.strongswan.org/projects/strongswan/wiki/FAQ#Aggressive-Mode
# see https://wiki.strongswan.org/projects/strongswan/wiki/IKEv1CipherSuites

#include /var/lib/strongswan/ipsec.conf.inc

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#include /var/lib/strongswan/ipsec.secrets.inc

@GroupVPN @<UniqueFirewallIdentifier> : PSK <SharedSecret>
<MyUserName> : XAUTH "<MyUserPassword>"

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# ipsec statusall
Status of IKE charon daemon (weakSwan 5.7.2, Linux 4.19.75+, armv6l):
  uptime: 2 seconds, since Jan 28 19:02:33 2020
  malloc: sbrk 811008, mmap 0, used 468032, free 342976
  worker threads: 11 of 16 idle, 5/0/0/0 working, job queue: 0/0/0/0, scheduled: 0
  loaded plugins: charon test-vectors ldap pkcs11 tpm aes rc2 sha2 sha1 md5 mgf1 random nonce x509 revocation pubkey pkcs1 pkcs7 pkcs8 pkcs12 pgp dnskey sshkey pem openssl gcrypt af-alg fips-prf gmp curve25519 agent chapoly xcbc cmac hmac ctr ccm gcm curl attr kernel-netlink resolve socket-default connmark farp stroke updown eap-identity eap-aka eap-md5 eap-gtc eap-mschapv2 eap-radius eap-tls eap-ttls eap-tnc xauth-generic xauth-eap xauth-pam tnc-tnccs dhcp lookip error-notify certexpire led addrblock unity counters
Listening IP addresses:
    GroupVPN:  %any...<SW_IPaddress>  IKEv1 Aggressive
    GroupVPN:   local:  [GroupVPN] uses pre-shared key authentication
    GroupVPN:   local:  [GroupVPN] uses XAuth authentication: any with XAuth identity '<MyUserName>'
    GroupVPN:   remote: [<UniqueFirewallIdentifier>] uses pre-shared key authentication
    GroupVPN:   child: === TUNNEL
Security Associations (0 up, 0 connecting):

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GroupVPN policy/AdvancedVPN/Advanced SettingsFrom SonicWall log (most recent at the top):

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I have an Ubuntu server (18.04) running a copy of WordPress that I'm trying to access from outside my home network. I have port forwarding set up on the router and can access Apache quite happily. However, putting in the URL //xxx.ddns.net/wordpress results in my browser displaying the internal address of the server and, naturally enough, failing to connect. I'm pretty certain that there's something fairly simple that I'm missing. Allied to this is that I can't SFTP into the server from outside either. the connection is made but always fails with the password. Of course it all works fine on the LAN. Can anyone enlighten me as to what I'm doing wrong?

i using ifupdown for ubuntu 18 server
after reboot i can't login to server (virtual)
ping gateway is unreachable but all my lxd on this host is up and reachable.
ping of the server is unreachable
I have a Wordpress site running on a LAMP stack running in AWS EC2 that got compromised today. The hacker encrypted the small MySQL database with a Bitcoin address instead of the expected tables.

I would like to install some AntiVirus and Malware software as a future deterrent. It wouldn’t have done me a lot of good in this case, but I realized that the folks before me didn’t set this up.

1/ Do you have any recommendations for software that plays nicely with Amazon Linux (basically RedHat)?

2/ Do you have a favorite set of “go-to” installation and configuration instructions that you could share? I need something fairly simple to setup & automate updating heuristics and protecting the system.

Thanks for your help!
I find that some mail application can't connect to the Centos server occasionally. Reboot the clients apps and it may solve the problem.

Is there any setting on the Centos that I need to fine tune. Seem like it is related to the TCP connection for mail flow which is not properly tear down or establish ...

In an effort to ensure machines are syncing correctly across our network, I was able to figure out the correct query to ask Tanium to pull NTP times across the network on all Windows systems.  Now I'd like to target another search and pull NTP information from Linux machines too.   Windows stores NTP info in the registry, where would Linux store it?

  Computer Name
  Registry Value Data[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters,NtpServer]
FROM all machines WITH
  Operating System contains windows

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I need help to write shell scripting to generate random number between (0,2147483647) infinite loop, random number will change every run during loop
on my ubuntu 18 (lxd) i need to open port 389 for ldap
i used command ufw allow 389
and check firewall the port is open.
from remote i connect telnet "my_server_ip" 389
connection refused
i stop firewall in in "my_server"
and try from remote : telnet "my_server_ip" 389 : still connection refused
(port 23 for telnet is open) what is wrong.
from server self telnet "server_name" 389 is working

from remote
nmap "my_server_ip" -Pn 389

Nmap scan report for 389 (
Host is up.
All 1000 scanned ports on 389 ( are filtered

Nmap done: 2 IP addresses (2 hosts up) scanned in 4.19 seconds

but nmap "my_server_ip" -P 389

show all open port and 389 is not there.
Dear All,

   I have a Centos 7 server, and running a image app and iPad is connecting to the centos server to view the images, just wonder any command in centos can check whether iPad is connecting to this server ? any help would be appreciated thanks

i try to join jenkins in freeipa ldap.
it return erroe: javax.naming.AuthenticationNotSupportedException: [LDAP: error code 48 - Inappropriate Authentication] (show details)      
i try ldap://ldap.company.local:389






Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.