I am debugging an issue with Unbound (DNS Resolver software) on CentOS Linux release 7.5.1804 (Core). I have 2 VMs in different environments that are supposedly running the same Unbound software.
[root@vm1 ~]# rpm -qa | grep unbound
unbound-libs-1.6.6-1.el7.x86_64
unbound-1.6.6-1.el7.x86_64
And:
[root@vm2 ~]# rpm -qa | grep unbound
unbound-libs-1.6.6-1.el7.x86_64
unbound-1.6.6-1.el7.x86_64
Both VMs are CentOS 7.5.1804 (I checked /etc/redhat-release
) and are running the latest kernel available for CentOS: kernel-3.10.0-862.14.4.el7.x86_64
.
Both VMs have enough CPU, RAM, HDD space.
VM1 was instantiated from a minimal ISO CentOS, while for VM2 I don't remember.
Both VMs have ~600 rpm packages installed (if that matters at all). They differ in rpm packages, but all the rpm packages they have are the latest ones available (yum update).
Both VMs have the same unbound*.service
files, the same unbound.conf
file and the same files and directories in /etc/unbound/
.
The problem I have is:
systemctl start unbound.service
(orrestart
) on VM1 takes ~1 minute to complete.systemctl start unbound.service
(orrestart
) on VM2 takes 1-2 seconds to complete.
I am not sure what is happening.
What could be the problem with VM1? How do I debug a problem like this?