Extend disk with LVM

Here is a quick walkthrough showing you how to expand an LVM volume or partition in Linux by first resizing logical volume followed by resizing the file system to take advantage of the additional space.

Note: In this example, we are working in Ubuntu, some commands may differ in different Linux distributions.

DISCLAIMER: Make sure that you have proper backups in place before starting out with the resize procedure on your VMs! Create any backups necessary to ensure that if something goes wrong you can always go back to a previous working state. Losing any information or wiping out your disks is all your fault if this happens. Using this procedure is all at your own responsibility.

If you are unsure about LVM and its components I will suggest you read a bit upon it. There are tons of articles, for example on Digital Ocean.


This process can be easy to do with LVM as it can be done on the fly with no downtime needed, you can perform it on a mounted volume without interruption. In order to increase the size of a logical volume, the volume group that it is in must-have free space available. It goes as follows.

  • Add more space from the hardware level. Either raid controller, or hypervisor.
  • Resize your partition to contain the extra space
  • Resize the PV in LVM
  • Expand the LV in LVM
  • Resize filesystem

To view the free space of your volume group, run pgdisplay command as shown below and look at the “Free PE / Size” field, in this case non-free.

Since we have added more space from the hardware level need to grow the partition. This is done by deleting it and create a new one that is starting from the same sectors but where the new partition uses more sectors than before. In the output beneath we can see how to extend the partition.

The disk partition is now extended. We need to inform LVM to grow its PV

Now we can verify that there is available space to grow LV.

Lastly, we grow the LV and extend the filesystem.


We have now successfully expanded a file system and corresponding LVM logical volume without any downtime. This was done by first expanding the partition of the disk, then the logical volume and finally performing an online resize of the file system.

No servers were harmed doing this procedure 🙂

macOS TFTP server

I have never really found a good TFTP for macOS. Is it funny that macOS is much used by network people but there isn’t a decent TFTP server?

Well, there is. macOS has it built-in, no GUI though. But that’s also fine, as long as you know to use it. It’s disabled by default, but you can start and stop it with the following commands.

The TFTP daemon uses the /private/tftpboot folder so we are going to copy the file there. Then set the correct permissions on the file.

There is a gotcha with the TFTP daemon, which is you cant copy a file to the TFTP daemon if that file does not already exist there.  To work around it you can just create a file and set the permission for it. Then your devices will just send data into the pre-created file.

Change Veeam job repository

Having to move jobs to another repository is something that can be time-consuming. If you have to do it with the existing job you will need to disable the job, move the data to the new location, point the job to the new location and then enable the job again.

I found the other approach to creating new jobs easier. You can do it in the GUI, but when having 200+ jobs it could take some time. Instead, I did a small script to list all jobs located on the old repo.

The script also looks a the retention point and writes into the old job that is can be deleted after x days. If you have very long retention then this way is not feasible and you will probably have to move data and point exing job to the new location.

Hope somebody else can use it 🙂

NSX API – DLR L2 bridging

Here is a script for mass DLR L2 bridge creation. I had to bridge a couple of hundred VLAN to VXLAN, and while it was maybe faster to create it by hand I would not have learned anything.

The script is reading from a CSV file where I have all my info. Then loops through the entries and create a distributed port group and then initiates an L2 bridge. The VXLAN had been created post to this operation.

Veeam repository with local account

For the matter of security, I consider it a good idea to isolate the Veeam repository server from Active Directory. So that a compromised domain admin account or other can not gain access to the repository.

But when wanting to do add the repository to the VBR its failing and saying “Access Denied”.

Alright, a bit of googling and found a short and precise article from another guy having solved this problem.

What was the solution?

Open regedit on the repository server and navigate to following

Here you add a DWORD with the name of “LocalAccountTokenFilterPolicy” and value of “1”. This fixes the problem and without rebooting.

Now you can add the repository server to the VBR. I always forgot where to find the info for the reg hack, so now it’s here so future Jesper can find it 🙂

APC 7920 PDU Console

Short post – needed to reset password on a APC PDU. Only way to do this was getting a console cable, of cause this cable is a proprietary cable of APC and not within my reach when you need it.

So found the pinout and did a little DIY. Pinout is as in the table

APC RJ12 PinDB9 Pin
1 Not used1
2(GND) Yellow5 (GND)
3 Green2 (RX)
4 Red3 (TX)
5 (GND) White5 (GND)
6 Not used1

RJ12 pluged into PDU and connected to jump wires. White and yellow is GND. Green
DB9 male console cable. White is GND pin5. Gray is TX pin3. Black is RX pin2.

Press and hold the reset button of the APC PDU. Wait for Orange LED to blink and press reset again. Check console for login each sec. When it respons you have 30 sec to login with apc/apc and reset the password.

Killing a virtual machine the esxcli way

Rarely I run into a ghost VM. I can’t do anything with the VM from vCenter or local UI for the ESXi host. It looks like it’s powered off but in fact, it’s still running in a sort of ghost state. You can vMotion all VMs of and reboot that hosts that the ghost VM is on. Sometimes its standalone hosts and then killing the VMs world with esxcli is easier.

  1. Connect to the ESXi host with ssh
  2. Get a list of all running VM worlds
esxcli vm process list

3. Identify the world from the output and take note of the World ID. From here we will kill the world. Start with type soft and then escalate it if it doesn’t work.

esxcli vm process kill --type=[soft/hard/force] -–world-id=ID

VM should now be killed, the VMX files are unlocked and you can manage the VM with the GUI tools again. If it didn’t work then you are left with the option to reboot the host containing the ghost VM.

NSX 6.3.6 to 6.4.5 – Controller problem encountered

NSX upgrades can be a delicate thing to upgrade, even though everything is in its finest shape.

After we successfully have upgrade the NSX managers we proceeded with upgrading of the NSX Controllers. We did pre-check and issued command “show control-cluster status” and it looked fine, upgrade to 6.4.6 went well and we could vMotion VMs around after the controller was booted. But post-checks was not ok, the “show control-cluster status” did not return as expected and we where not confident to proceed with the host upgrades.

After some trouble shooting we found that the /var/log partition on 2/3 of the controllers where full. Without any other evidence we concluded that this was the problem. After some google-fu we didn’t find any KB or blogs on how to purge logs.

But we found out that we could get into a engeering mode that would give us shell access. Long store short, we did the following:

1. https://kb.vmware.com/s/article/2149630 to gain shell access on manager
1.1 password is IAmOnThePhoneWithTechSupport
2. Extracting root passwords for controllers with /home/secureall/secureall/sem/WEB-INF/classes/GetNvpApiPassword.sh controller-nn
3. Loged into each controller, and issued : debug os-shell and thereby gain root shell access.
4. Deleted /var/log/syslog.1 on each node.
5. Rolling restart of controllers and after they booted they all joined the cluster.


After this we got the status as we wanted. In the mean while we had create a case with VMware support and the supporter was on a remote session with us. We told him what we have done, we verified that the controlleres was health and they where.

Next step, VIB upgrade on the hosts.

Good commands to know:

Edit: This article from VMware have the exact problem we encountered. We also contacted VMware Support, but before they where able to assist us we had the problem solved. 🙂

Process of getting the root password for controllers.

Tomcat9 and java12 on FreeBSD

Quick post, had to make Tomcat9 and Java12 work together. The procedure is as follows:

1. pkg install tomcat9 (it will also install java8)
2. pkg install openjdk12

Now and edit /etc/rc.conf with a parameter to start tomcat on boot and set the tomcat java_home.

And not to part that took me a long time to figure out. In Java12, there is no longer a feature that tomcat is using in its startup parameters. But if you remove that from the init script you are able to start it up. The line is: Djava.endorsed.dirs=’/usr/local/apache-tomcat-8.0/endorsed’ \

After this, you are now able to boot tomcat9 with java12 🙂

Getting all domains from Office365 tenants

Mail spoffing etc. is a big problem, there are technologies that can help, but many domain owners have not yet implemented them. To help our customers we have started to monitor and see if the SPF, DKIM and DMARC policies have been implementened, and if not we can help 🙂

Our own spamfilter solution have a button that gives you an export over all the domains, nice and easy, but Office 365 CSP portal doesnt.

So there is a quick script to help with that. Next post will hopefully contain the checkscript for if the domain have implemented SPF, DKIM or DMARC.

NSX Edge PowerShell manipulation

This is from a VMware support experience. A customer could not change DNS server parameters of the NSX Edge IP Pool. But actually is was a problem due to a bug in VCD 9.5, where a Edge XML config was missing some tags and therefor not being able to validate the XML when VCD post the edited XML config back to NSX manager.

I have attached VMware support answer in the bottom of the post.

Script will get all edges from the NSX manager, then you find the correct one and fill into the next part of the script. Then you get the XML down to a file on your local machine, you then edit the file and put in the missing tags and lastly PUT the XML backup NSX manager. After this operation, it works from the GUI again.

From Support:
– The issue you are seeing is a known issue 9.5.
– Like I mentioned in the previous email, this is due to missing elements from the xml.
– From the xml in the logs, I could see there are 52 NAT rules on that edge.Correct me if I am wrong. The following 2 rules had the elements missing

I have attached the file with the list of all the NAT rules seen from the logs if you need to cross-verify.

– To fix the issue,please follow https://kb.vmware.com/s/article/67193

If you have any further questions,let me know.

Have a good evening,

Best regards,


Make a clone of VMs to NAS – The PowerCLI way

Quick post, had a customer that yearly wants a clone of their VMs, copied to a NAS, and then shipped to customers HQ. The owner of the company put this as a requirement. Fair enough. I have almost always done the clone of the VMs by GUI, in the start, this was easy because they only had 5 servers, but they now have more. So this time I wanted to try and script it instead. It took me some extra time, but in the end, I think it’s worth it. My PowerShell skills are not great, still learning so bear with me.

FreeNAS installation failed – Operation not permitted

Ran into an annoying problem, have been having this problem multiple times in the past, and never remember what the fix is. So now it’s on the blog for the next time that I need it. Use the shell option in the FreeNAS installer, the disks that I wanted to install onto was ada0 and ada1.

1. sysctl kern.geom.debugflags=0x10
2. dd if=/dev/zero of=/dev/ada0 bs=512 count=1 && dd if=/dev/zero of=/dev/ada1 bs=512 count=1

This will wipe out the sectors that keep the partition schema and afterward, you can install FreeNAS without problems.

ESXi – physical memory population

Had en interesting problem where a ESXi host only showed it had 30GB of memory, but the motherboard was populated with 6*8GB modules. In earlier versions of ESXi 5.5< it was possible to use dmidecode to show how the physical hardware was populated. But since 6.0> that have been removed.

The new command to find those kind of information are now “smbiosDump”

You can also just run smbiosDump without any paramenters and you get a hole lot of information to crawl through.

Timedrift – domain controller and clients

Customers domain controllers where both virtual and due to CPU congestion it seems that time had been drifting.

So it was 5 minutes behind, and so was the clients. The fix is as follows.

1. Find the DC that have the PDC role.

2. Issue the follwing command to sync the time with some of the pool.ntp.org servers.

3. After the time on the PDC again is correct, then issue following on the other domain controllers, that are not PDC.

4. let the clients resync there time, either wait for it to happen or issue the following

Freebsd – Going from stable to release

I outdated FreeBSD 10.1-Stable server needed to be updated for it to install packages again. Problem was, it was deployed from stable, i normally never use stable because it not production ready, its a development branche. But this server was stable and here are the steps to get it to a release train.

1. Update the source tree on the server.

2. Follow the link below. Only change i did was to “-j 6” when making so that it used multiple cores.

After the merge-ui command you just choose “later” for all the promt with merge of config files.

And volia, The server is updated to FreeBSD 10.4-release. Then you can update with the binary process, freebsd-update upgrade -r 11.2-RELEASE.

In case you need to know more about the stable vs. release, here is a link i found en the FreeBSD forum.

P2V of a FreeBSD

Was looking for someone that had done a P2V of FreeBSD, but me google skills was not good enough. So here it goes.

1. Make a VM with disk a bit larger then the source phycial machine.
2. Boot the VM on a FreeBSD live cd
3. Give it a IP address

4. Make NC listen for any input on port xxxx ( )

5 on the physical maskine you run DD and pipe it to NC.

6. wait for it to finish….

Ceph – slow recovery speed

Onsite at customer they had a 36bays OSD node down in there 500TB cluster build with 4TB HDDs. When it came back online the Ceph cluster started to recover from it and rebalance the cluster.

Problem was, it was dead slow. 78Mb/s is not much when you have a 500TB Cluster. So what to do?

There a several settings within Ceph you can adjust. Here are the two settings that worked for me.

osd max backfills:
Description: The maximum number of backfills allowed to or from a single OSD.
Default value: 1

I set it to 8, and the recovery went to 350Mb/s. Set it to 16 and recovery was 700Mb/s, but clients where also affected. So 8 was a more moderat setting.

osd recovery max active

Description: The number of active recovery requests per OSD at one time. More requests will accelerate recovery, but the requests places an increased load on the cluster.
Default value: 3

Set it up a notch to 4.


Mysql replication

Had to resync master-slave replication setup. Here are my notes on how it’s done.

Binary bin-log files are kept for 7 days on DB1. If the replication is stopped for more than a week DB2 replication cannot start again due to the binary log files is no longer available. therefor a fresh dump is needed and DB2 replication can be started again from the master log position.



  • Single-transaction, makes it possible to do the dump without locking the database, very useful when having to dump from a production database. But while not locking the DB you may not create or alter table schema.  Mysql documentation link
  • master-data, is very useful because it records the master position when doing the dump and putting it into the output of the dump file. Therefore it is much easier to start the slave from the correct position. The number 2 is for only printing it to the output as a comment. Mysql documentation link
  • event and routines, if there are any stored procedures or like in the old server we take them with us. Mysql documentation link

mysqldump --single-transaction --quick --master-data=2 --events --routines <DATABASE> | gzip > /data/<DATABASE> _`date +%F`.sql.gz

When the dump is done we move the dump file over to the other server. Here we import it to the MySQL server if there already were an old database in place, drop it and create it again.
zcat <DATABASE>.sql.gz | mysql <database>

Also, have a look at the head of the dump file where we will find the master position data that we need to start the replication again.

gzip -cd <DATABASE>.sql.gz | head -n24

Now we have the position and need the user for replication. I did it on an older 5.5 database, in newer MySql servers it is done differently.


Or if the user is in place and you just need to reset the password:

When it is imported we need to setup the master to master(slave) replication again. Remember to have a user on DB1 that is allowing replication from the DB2 server and have the user and password ready CHANGE MASTER TO MASTER_HOST='<IP>',MASTER_USER='repl', MASTER_PASSWORD='happyS3ed99', MASTER_LOG_FILE='mysql-bin.000849', MASTER_LOG_POS=758329777 ;

It will now start to replicate from the master, now you can do a “mysql -e ‘show slave status\G'” and see if the slave IO is running as it should.


Rescuing a Juniper SRX550

Notthing more greate than getting a call from HQ 30 minutes after closing hours. Never the less i decided to take the call. Network problem onsite at customer…. After getting green light from women in charge, i got in the car an when on to the customer.

Connection with the USB cable to the SRX console port i got a weird boot sequence. Just like the following:

Either the Junos partition was corrupt or the disk inside of the unit was fried. Decided to try and install Junos again just see if that would help. Went to juniper.net and downloaded the oldest Junos version available, junos-srxsme-12.3X48-D10.3-domestic.tgz. Found a USB drive and put the .tgz file on it and plugged it in the SRX. From the console i broke the bootloader while its was trying to find kernel and issued the following command.

I began to install Junos, but when it tried to create partitions on the card, it died with DMA errors. Great!

Since a SRX550 is not something you find everyday and spareparts a hard to get (support was also expired) i decided to take the srx apart. happily to find a CF card inside and luckily i found a kingstone CF card in my bag (I knew that would come in handy someday). Swapped the card and put it together again.

Power on and issued the install command again. This time with success.

The install of Junos take sometime, a long time 20 minutes. But then you also get a very nice login prompt. logged in with root and no password. Went into cli configuration mode and did a “delete” to wipe the factory config. then loaded the backup configuration with

Pasted the 55kb JSON config into the console and finished with a ctrl+d followed by a commit. commit success and all network was suddenly alive again.

just to make all the LEDs green on the SRX i did wrote the config to rescue config. This is in operational mode.

A happy consumer and hopefully a new Juniper SRX1500 firewall on its way to relive the SRX550 off its duties.