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How to update Centos 5 .X and cannot find a valid baseurl for repo

Post author:Gkhan
Post published:August 27, 2018
Post category:Linux
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How to update Centos 5 .X and cannot find a valid baseurl for repo

If you are using CentOS 5.x and want to install any software and update CentOS 5.x . you are getting following error .

root@server1 [~]# yum update -y
Loaded plugins: fastestmirror
Determining fastest mirrors
YumRepo Error: All mirror URLs are not using ftp, http[s] or file.
 Eg. Invalid release/
removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt
Error: Cannot find a valid baseurl for repo: base

This is because update repositories were moved to the CentOS vault when the operating reached it's end-of-life.

Edit the following file

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vos3000 illegal calls query to block IP address

Post author:Gkhan
Post published:August 23, 2018
Post category:VOS3000
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vos3000 illegal calls query to block IP address All call records are saved in e_cdr_files you can query to get ip addresses of illegal calls source. mysql> select DISTINCT callerip…

How to configure Mikrotik DHCP Server for Cisco Phone TFTP option

Post author:Gkhan
Post published:August 7, 2018
Post category:Uncategorized
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How to configure Mikrotik DHCP Server for Cisco Phone TFTP option

1- Change your TFTP server IP in to hex code

you can use this online tool : http://www.miniwebtool.com/ip-address-to-hex-converter/

2- Now configure Mikrotik RouterOS :

/ip dhcp-server option add code=150 name=ciscotftp value=0xC0A80307

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How to install VMware tools in Linux Virtual Machine

Post author:Gkhan
Post published:July 19, 2018
Post category:VMware
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How to install VMware tools in Linux Virtual Machine

Make sure Linux virtual machine is powered on.
Click VMin the virtual machine menu, then click Guest > Install/Upgrade VMware Tools.
Click OK.Note: In some cases, verify that the CDROM device is Connectedfrom within the Edit Settings option of the virtual machine.
To create a mount point, run:mkdir /mnt/cdrom
To mount the CDROM, run:mount /dev/cdrom /mnt/cdrom

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OpenVPN CRL has expired

Post author:Gkhan
Post published:July 15, 2018
Post category:Linux VPN
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OpenVPN CRL has expired VERIFY ERROR: depth=0, error=CRL has expired: CN=servername In order to fix the issue, we just need to recreate the crl.pem file. we need to backup the current crl.pem…

OPENVPN Logs

Post author:Gkhan
Post published:July 15, 2018
Post category:Linux VPN
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OPENVPN Logs To troubleshoot connection issues check below logs grep the client name in /var/log/messages # grep VPN /var/log/messages Check the connection time #cat /etc/openvpn/openvpn-status.log Check the connection negotiation…

How to install vos3000 2.1.4.0 on CentOS 6.X

Post author:Gkhan
Post published:February 8, 2018
Post category:VOS3000
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How to install vos3000 2.1.4.0 on CentOS 6.X

Follow the steps

#/etc/init.d/iptables save
#/etc/init.d/iptables stop
#chkconfig iptables off

#/etc/init.d/ip6tables save
#/etc/init.d/ip6tables stop
#chkconfig ip6tables off

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VMware OS Optimization Tool

Post author:Gkhan
Post published:January 23, 2018
Post category:VMware
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VMware OS Optimization Tool The VMware OS Optimization Tool helps optimize Windows 7/8/2008/2012/10 systems for use with VMware Horizon View. The optimization tool includes customizable templates to enable or disable…

SSH Login Email Alerts

Post author:Gkhan
Post published:December 7, 2017
Post category:Linux
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SSH Login Email Alerts The examples below send an email when someone logs into your server. For this to work, your server must be able to send mail using the mail command.…

iptables port forwarding

Post author:Gkhan
Post published:November 6, 2017
Post category:Linux
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iptables port forwarding

I am port forwarding public ip x.x.x.x to private ip 192.168.200.200 .

iptables -A INPUT -i eth0 -p tcp –dport 5001 -m state –state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -o eth0 -p tcp –sport 5001 -m state –state ESTABLISHED -j ACCEPT
iptables -t nat -A PREROUTING -i eth0 -p tcp -m tcp –dport 5001 -j DNAT –to-destination 192.168.200.200:5001

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