Starting VM after update Ovirt node

So I upgraded oVirt node to 4.2.6.1 version. After upgrade I was presented with not being able to migrate VM or run VM on the node. I did go in engine logs and vdsm logs. I found bunch of errors but one did stand out 2018-10-04 13:55:57,810-0400 ERROR (vm/8917a3f3) [virt.vm] (vmId=’xxx-xxx-xxx-xxx-xxx’) The vm start process […]

Gluster tips

Here are some small tips which might be helpfull. Good to specify _netdev mount option under /etc/fstab since we need network to be up for accessing gluster volume. Without this option when booting startup scripts will try to mount filesystem before networking was started. Gluster has an option backup-volfile-servers which is used when a gluster […]

Migrate rootvg on VIOS and on LPAR

Recently I was tasked to work on VIOS and LPAR and here is some notes for me to remember. ====Identifying the Newly Added Disk(s)==== NOTE: If this is a dual VIOS setup, the commands must be done on each VIOS unless noted otherwise. On the VIO Server: List all physical volumes on the VIOS: $ […]

oVirt Change master storage domain

Using oVirt and needed to change our master storage domain to another fibre channel attached SAN. Here is what I needed to do in order to get this changed. Stop all VMs Place all storage domains in to maintenance mode except ones you want to swap Now place your master domain in to maintenance Now […]

Gluster brick configuration

I simply used a physical device as my brick for Gluster. Create a LVM layer. Redhat advises to align the I/O at the LVM using –dataalignment option. Way to calculate alignment_value is by multiplying the raid stripe unit size with the number of data disks. So for example on a 12 disk raid 6 configuration […]

Kerberos Client trace

If you are trying to debug kerberos on client side there is not a lot of options for you. You can position the KRB5_TRACE environment variable, standard system out may help you on this case! KRB5_TRACE=/dev/stdout kinit emre [5753] 1494515577.97906: Getting initial credentials for emre@zenteric.com [5753] 1494515577.102972: Sending request (178 bytes) to zenteric.com [5753] 1494515577.103031: […]

Save a readonly file while you are still in Vim

I was doing this and a coworker of mine saw it and told me that is a cool trick so it became a blogpost. :w !sudo tee %:w !sudo tee %

How to add glusterfs to ovirt (rhev)?

I have 10 node trusted storage pool. I created a distributed replicated volume on it called emre-vol1 with replica count 2 [root@gluster01 ~]# gluster volume status emre-vol1 Status of volume: emre-vol1 Gluster process TCP Port RDMA Port Online Pid —————————————————————————— Brick gluster01.peakox.com:/gluster/bric k_ssd/brick 49152 0 Y 172197 Brick gluster02.peakox.com:/gluster/bric k_ssd/brick 49152 0 Y 103826 Brick […]

Display the contents of a SSL certificate

I was asked couple times last week and today about to display the contents of a ssl certificate. You can display the contents of a DER formatted certificate using this command under linux using openssl: $ openssl x509 -in mycert.der -inform der -text and for contents of a PEM formatted certificate under Linux, again using […]

Resize a qcow2 harddrive images

I have been dealing with disk images a lot recently, I make the hard drives on my virtual machines as small as possible because I believe its easier to extend then shrink. Since I do have lvm on my systems and use xfs this has been really easy for me. Here is a quick excersize […]

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