I had old UPS with serial port which was connected using Profilic USB to serial adapter. Sometimes this USB dongle had frozen and need to be restated – re-attached. This can be done in linux using IOCTL.
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After recent security updates, my webmin (now 1.903) served trough haproxy stopped working. Login page was not loading correctly… Continue reading
There has been some comments in my old posts trying to use generated country lists in Apache .htaccess. This approach is wrong, and I will show you much better way how to block or allow specific country.
This my blog and also other hosted websites running WordPress are target of bots trying passwords to wordpress admin and posting spam comments. I was unable to found simple plugin for comments dns blacklist, so I focused to mod-security. Continue reading
If you have big XFS filesystem (with lot of files) and you use inode64 mount option, exporting this file system using NFS may fail when mouting this export on client:
Stale NFS file handle
This error is strange and confusing. Workaround is to specify fsid in /etc/exports for this filesystem.
For more information check this nice blog article https://hpc.uni.lu/blog/2014/xfs-and-inode64/
Backup in virtualized enviroment is mostly based on snapshoting entire virtual machine and saving this state to backup repository. This snapshot does not include memory of virtual machine. When you restore virtual machine from this snapshot filesystem is in unclean state, but journal filesystem can handle this. From mysql point of view server crash happended and database can be corrupted and unrecoverable, depending on what queries where running during snapshot. This unpredicted and unconsistent state you don’t want to have as a backup of your data. Continue reading
I have been searching for simple and easy script to backup selected virtual machines running on esxi server, which will:
I was unable to find any to comply my requirements. I’m learning python, so I searched for some python vsphere libs and found psphere. Then backup.py has born.
Are you getting angry when installing Debian and your network cards (eg. bnx2) are not working because of missing non-free firmware policy? Solution is simple – just use for installation unofficial Debian iso images with firmware. Continue reading
VMware vSphere cli requires many CPAN libraries. On Centos 6 I have enabled EPEL repository and installed packages:
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IPSec implementation has been changed in recent Redhat Enterprise Linux (RHEL) from ipsec tools (used in RHEL 5) to openswan in RHEL 6. Configuration using ifcfg-ipsec interfaces doesn’t works any more. Obviously, same change applies for Centos.
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