OpenVPN CRL has expired

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 file before creating a new one.

The location of the  crl.pem file  at /etc/openvpn/

#mv  crl.pem  crl.pem.back

Now go to  easy-rsa  folder

# cd  easy-rsa

now generate crl.pem

./easyrsa gencrl

Now copy the new crl.pem to openvpn folder

# cp pr /etc/openvpn/easyrsa/pki/crl.pem

Now restart openvpn service


source link :-


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 activity

# tail -f /var/log/messages


VMware OS Optimization Tool

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 Windows system services and features, per VMware recommendations and best practices, across multiple systems. Since most Windows system services are enabled by default, the optimization tool can be used to easily disable unnecessary services and features to improve performance.

You can perform the following actions using the VMware OS Optimization Tool:

  • Local Analyze/Optimize
  • Remote Analyze
  • Optimization History and Rollback
  • Managing Templates

Download latest  VMware OS Optimization Tool

iptables port forwarding

iptables port forwarding

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

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

Continue reading iptables port forwarding

How to configure UCCX Simple Auto Attendant

How to configure UCCX Simple Auto Attendant

I  am going to configure UCCX and CUCM for simple Auto Attendant using inbuilt script (aa.aef) in Cisco UCCX. I am not making any restriction so I am not using CSS and Partition to make it very simple .

we need to go through following steps .

  • Creating UCCX Call Control Group (CTI Ports in CUCM)
  • Adding  UCCX Script Application
  • Adding UCCX Trigger (CTI Route Point in CUCM)
  • Make a Test Call to Auto Attendant

Before going above steps  UCCX basic configuration  should be done as AXL, JTAPI and RMCM integration. As it is the POST  UCCX configuration after installation  .

Continue reading How to configure UCCX Simple Auto Attendant

How to configure MGCP on Cisco Router and CUCM

How to configure MGCP on Cisco Router and CUCM

To configure MGCP  on Cisco Router and CUCM below are the steps

1- Configure  E1 or T1 Port to work with MGCP

2- Configure Router for MGCP to register on CUCM

3-Configure CUCM


For step 1

Follow the link

Step -2

mgcp call-agent service-type mgcp
mgcp bind control source-interface FastEthernet0/0.110
mgcp bind media source-interface FastEthernet0/0.110
mgcp dtmf-relay voip codec all mode out-of-band

Continue reading How to configure MGCP on Cisco Router and CUCM

How to configure Cisco Router T1 for MGCP

How to configure Cisco Router T1  for MGCP

Below steps checked on  Cisco 2811 and 2911 Routers

1- Check the  VVIC  location

R1#sh inventory
NAME: “2811 chassis”, DESCR: “2811 chassis”
PID: CISCO2811 , VID: V05 , 

NAME: “VWIC2-1MFT-T1/E1 – 1-Port RJ-48 Multiflex Trunk – T1/E1 on Slot 0 SubSlot 0“, DESCR: “VWIC2-1MFT-T1/E1 – 1-Port RJ-48 Multiflex Trunk – T1/E1”


Show inventory command shows you the location installed VVIC card in our case it is installed on Cisco Router Slot 0.

Continue reading How to configure Cisco Router T1 for MGCP