Joerg Moellenkamp

Joerg Moellenkamp

98 Posts

Grey-haired, sometimes grey-bearded Windows dismissing Unix guy.

Solaris 11.4 SRU 60: Sample separation in iostat

As i had quite a fight with a larger IKEA PAX closet for my bedroom, i hadn’t quite the time to complete the ZFS retention article so far. Thus today a small...

Solaris 11.4 SRU 66: Precision of logfile timestamps

Another rather small change that was introduces to Solaris 11 in SRU 66. Up to SRU65 the precision of the timestamps in the logfile was seconds. Jul 5 06:1...

Solaris 11.4 SRU 57: Why did you reboot the system?

Yet another small addition to Solaris 11.4. This one was released with SRU 57. reboot, shutdown and poweroff got a new option. With -c you can now specify a...

Solaris 11.4 SRU 60: admhist shows SMF audit records

Yet another small feature. I’m working on a blog entry about ZFS retention in the evenings, but it will take some time to complete it. So a blog entry about ...

Solaris 11.4 SRU 63: Disabling reboots (temporarily)

I’m not allowed to watch games of the national team of Germany. Currently Germany is playing against Spain. Friends and family have forbidden me to watch the...

Solaris 11.4 SRU 69: Including file fragments in ssh configuration

While the last blog entries were about cycling, I would like to start with Solaris centric blog entries as well. My plan is to write without a planned schedu...

Umbau

At first a note to my reader in English language: In the future, only blog entries about Solaris and IT in general will be in English language. Everything e...

Solaris 11.4 support available until at least 2037

There is an important note in footnote 7 on page 40 of the “Oracle and Sun System Software and Operating Systems - Oracle Lifetime Support Policy”: “As a res...

Beware of assumed simplicity

I’m currently sitting at my desk looking to an heap of cables. Display cables. You don’t think too much about display cables. At least i did not think too mu...

Probably just an overengineered small keyboard

(This is a test blog entry (based on a text I started a while ago) for the new Jekyll workflow) Sometimes you see a device which results in a “Must-have” re...

2023

Peter Gabriel hat dieses Jahr wieder ein Album herausgebracht. Ich hatte eigentlich schon die Hoffnung verloren, das “I/O” je herauskommen würde. Denn Herr G...

From cycling to computer systems performance – Part 1

This is my first longer blog entry after getting back to a more frequent blogging schedule. It will be a two part blog entry. It may start with cycling, howe...

Problems of a vegan

I’m vegan for a while. I’m not a health vegan, because it’s perfectly possible to eat totally unhealthy as a vegan. I’m the living proof. I’m not really doin...

Thoughts about PoE security cameras (and outdoor ethernet cables in general)

I’m currently trying to buy a security camera, because i have the suspicion that people are using my property as a shortcut. I had just one thought: There ar...

Koblenz ... again ???

I’m back from Koblenz. My brother asked me to help to fetch something from this town and as was on a weekend and i’m on vacation the obvious answer was to a...

Changing Unifi inform URL via SSH

My house has four Ubiquti Unifi AP-AC-LR access points. Out of whatever reason, the construction of the house seems to attenuate WIFI signals significantly f...

Cable management

Today i was quite occupied by a search mission: As absence of a proof is not the proof of absence, I was searching for things and I had no proof to myself th...

Feuer&Flamme

I’m currently working on a longer blog entry about measuring systems performance, but this will take some additional days. Meanwhile i would like to point yo...

Strangest things

I have seen and experienced a lot of things when driving on the Autobahn through Germany. I have seen quite a few crashes, smaller and larger ones. To this d...

Suspiciously new

I wrote this morning that my house has currently no VDSL internet, just cable internet. I’m just back from the street in front of my home. Roughly 50m away t...

Redundant

The street in front of my house gets a new cycleway on the inbound side of the street. While this is a really great idea because the old one was in an abysma...

Docking

I wanted to get rid of a significant set of cables when I set up my new desk, there were a gazillion of cables flying around on my desk and I wanted to bring...

Nothing changed …

As if the the last few years didn’t happen? Was at the supermarket this morning. People sneezing, people coughing, nobody wears a mask, even those people who...

Keeping my stuff together

In case you wonder about my recent uptake in blog entries and in entries about recent purchases, this is at foremost currently getting back into the writing ...

Age

You get vastly more aware of your own aging when you listen to live music on youtube from musicians roughly your own age and look at them changing over time....

Workarounds - revisited

The example with the heating system is a better example than I thought. I learned some additional things over the course of the day. There are workarounds, ...

Workarounds

Sometimes you may think that IT is the only business where workarounds are used. Today i was reminded that other businesses do the same and some even make pr...

Keyboards

It’s roughly 20 years ago that I’ve switched to use notebooks for work. Before my time at Sun i was able to convince my manager that i really needed the Powe...

Åskväder

A few days ago, I needed some distraction and thus I drove one of my sisters to IKEA. I needed a desk lamp1 anyway and thus this looked like a good idea. At ...

Xodus

A while ago i left X (the website formerly known as Twitter). I assume out of the same set of reason why most people i know left Twitter. I really loved it...

Cleanup

I’m just in the process to clean up the blog and updating some static pages. The cleanup was nescessary to be able to run the scripts to publish new blog ent...

2022

Hier sitze ich wieder auf meinem Sofa und sinniere über das letzte Jahr. Das Fernsehprogramm ist noch schlechter als sonst. Hinzu kommt, dass am heutigen Tag...

The joy of solving performance problems - Part 1

It took me some more time to have this first part ready, because I revised it quite a lot and in the recent evenings i didn’t wanted to spend the nessesary t...

The joy of finding performance problems - A foreword

A journey Many interesting journeys start with a first step. There are lessons in them and no matter how much you have seen in the past, you always learn new...

Visualize

„The Matrix“ ruined it a little but for all of us. Outsiders have sometimes the impression that admins can find errors on their servers just by staring at t...

Zebras, anchors, bottlenecks and link aggregation

Diagnosing problems with computers has a lot to do with diagnosing illnesses (that’s the reason why I’m working on an article about patching and vaccination ...

2021

Ich sitze hier gerade an meinem Schreibtisch und wundere mich, das selbst in einem Jahr, in dem es eigentlich empfohlen ist, zuhause zu bleiben, es lediglic...

Rest in peace, Joerg Schilling

Just saw the notification that Joerg Schilling, the creator of the cdrtools and Schillix (and many other tools), passed away this Sunday. He was one of the w...

Additional information for your zone configuration.

Sometimes it’s useful to enrich your zone configuration with some additional data, so someone can look into the zone config and know for example who is respo...

Changing passwords - re-revisited

There was an interesting question on Twitter after i published my blog entry about assigning the authorization to change passwords to regular users: “Can you...

Changing passwords - revisited

You are an quite busy admin. The systems are well kept. Everything is working fine. However many people work on your system and inevitably some people forget...

Changing passwords - revisited

You are an quite busy admin. The systems are well kept. Everything is working fine. However many people work on your system and inevitably some people forget...

Changing passwords

This is a blog entry from the category “Just because you can do it this way, you should not nescessarily do it this way” albeit the biggest problem with usi...

S11.4CS: General Administration - Packaging

Oracle Solaris 11.4 General Administration Packaging Install a package called diagnostic/wireshark: # pkg install diagnostic/wireshark Install a gr...

S11.4CS: General Administration - Boot Environments

Oracle Solaris 11.4 General Administration Boot Environments Boot Environments are individual bootable instances of the operating system that take advantage ...

S11.4CS: General Administration - Users and roles

Oracle Solaris 11.4 General Administration Users and Roles Revert root to a normal user account # rolemod -K type=normal root Configure root as a ...

S11.4CS: General Administration - Locales, timezone and keyboard

Oracle Solaris 11.4 General Administration Locales, Timezone and Keyboard Get current configuration # nlsadm get-console-keymap # nlsadm get-system-lo...

Solaris 11.4 Cheatsheet

Starting today i’m beginning the next part of my brain dump project. I will port the Solaris 11.3 Cheat Sheet which i wrote to some extend some years ago int...

S11.4CS: General Administration - System Configuration

Oracle Solaris 11.4 General Administration System Configuration Common system configuration tasks have changed in Oracle Solaris 11 with the Service Mana gem...

Tiered storage with ZFS

This is another blog entry in regard of ZFS and about what you have to keep in mind about it, when working with ZFS. It’s nothing really astonishing, you jus...

vmstat without history

Historic values are sometimes quite useful to have an overview what’s happened in the past on your system, but quite often it’s only something you have to re...

Authorizations for Zone Console access - Part 3

Okay, there is one remaining obvious question. What if you have an admin that is responsible for all the systems and you want to give her access to all the z...

Authorizations for Zone Console access - Part 2

As i wrote yesterday, there is an alternate way to configure zone console access. Let’s assume we want to give the user junior the authorization to access th...

Authorizations for Zone Console access - Part 1

When you wanted to access the zone console on Solaris system as a normal user in the past, you needed an authorization. You may remember from a very old c0t0...

Increasing ZFS pool sizes

I had this discussion with a number of customers in the past, because it’s one of the not so obvious consequences of the inner workings of ZFS, of how ZFS al...

ptree with service names

A nice tool to get some understanding of the dependencies of processes is ptree tool. With the -c option the contract id (the contract filesystem is one of t...

newtask easier to use in scripts

newtask is an important tool when you start applications in a different project context, for example for resource control purposes. May be you may remember m...

Enterprise Health Check

(This blog entry was in the publication queue for a while, so Chris Beal overtook me with his great blog entry) For a very long time there are some security...

More precise timestamps for DTrace

Sometimes the timestamps delivered by %Y are not precise enough for debugging purposes. # dtrace \ -n 'syscall::read:entry {printf("%Y", walltimestamp);}'...

How you have grown ... sxadm

I remember i have first talked at a Solaris day in the Vienna Urania about sxadm for security extension administration. At that time we had one security exte...

Improved debugging in LDAP tools and nscd

Some of this improvements are not really new. They were in Solaris for years, however they were not really documented and while many people knew about them t...

Lock it up

This is a quite useful tool. Let’s assume you are working with colleagues on a system on their desktop. They are working on their shells as unprivileged user...

Just the processing please

One of the many enhancements to well known tools like truss was the introduction of the option -G to said command. When you truss for a command with -E it sh...

truss - just the interesting part ...

Most of the time when trussing a process you are not interested in all the system calls that are working perfectly and which are scrolling by in high speed. ...

Servicename in ps

Yesterday i wrote in “prstat -x” about the addition of a feature to show the FMRI of the service which the process is part of. ps got a similar enhancement. ...

prstat -x

When looking with processes on your system, sometimes you ask your self “Who the heck started this process? Often it’s a process started by SMF as part of a ...

Oracle Solaris 11.4 SRU 31

SRU 31 of Oracle Solaris 11.4 has been published today. You will find more information about the changes here.

fsstat

The command fsstat (somehow a command relatively unknown when talking with customers) got a slight enhancement in an Solaris 11.4 SRU. Before this enhancemen...

Clean up after yourself

This is a rather small change in one of the Solaris 11.4 SRUs. SMF had so far three methods. You could have a start method, which is as the name says meant t...

Even more new options for svcbundle

Another addition to svcbundle was the addition to set user group privileges to directly create manifests for SMF that didn’t need manual editing to ...

Homedirectories

Even such venerable tools like useradd could use some extra features. In a recent SRU an option was added to set a default how the home directory is created....

iostat and microseconds

Solaris 11.4 got a small extension to the iostat command. In a time when storage storage gets faster and faster, you may end in a sitation where the wsvc_t a...

gcore with less impact

This isn’t a everyday tool, however for diagnosing problems gcore is one of the important tools in your toolbox. With gcore you can create a core image of ea...

ps

Today i won’t write a blog entry explaining a feature. I would just like to guide your attention to an article at “Teaching an old ps command new tricks” wri...

Jitter and delay for svcbundle generated SMF manifests

Another extenstion to the svcbundle tool is the introduction of -s delay= and -s jitter= for periodic SMF services services. If you have something to start i...

svcbundle extended

svcbundle is an really useful tool to create SMF manifestes without having to hassle too much with XML. Most often you don’t have to work with XML at all , b...

Which SRU to get those new features?

Short anwser: The newest one you can get on the day you are reading this. The long answer: All the features i’m writing about in the last few days didn’t ap...

New -s option for zpool status

With SRU 30 of Solaris 11.4, the zpool command got a new option for the status command. You can now get some additional information about the devices. This b...

ZFS allocation units

This feature introduced in Solaris 11 SRU 30 is really an interesting one. It’s nothing you should really need often because usually ZFS will do the right th...

You have been warned: Upgrading rpool

In the past customers painted themself into a corner, when they did a rather large jump with their OS versions, upgraded their app as well, upgraded the zpoo...

Solaris scales

This is a nifty small feature . Tools like ps,df,du, ls,ps,size,prstat and swap have now the option --scale. This makes the output of those tools much more ...

Limits revisited

There were more limits changed in regard of open files has been changed with as well. The change took place in SRU27. rlim_fd_cur has been increased from ...

Small changes : New open files default.

In a relatively recent Solaris 11.4 SRU a limit was increased in it’s default setting. In 11.4 (no SRU) the limit of of open file for a user was 256. root@s...

Solaris 11.4 and user_reserve_hint_pct

A long time ago, i wrote about the /etc/system-parameter user_reserve_hint_pct. It limits the size of the ZFS ARC cache by proxy by essentially limiting the ...

Homebridge and Tasmota at my cellar

And Darmok and jalad at Tanagra. As i integrated them into Homekit via Homebridge, i had the problem with the Delock sockets with their custom firmware that...

vHBA and AIO

In Oracle Solaris 11.4 SRU30 there was an important change with LDOMS you should be aware of as you probably have to do an administrative step to get best pe...

Piped sandboxes

I got one question via Twitter: “What if there were a convenient way to run typical Unix commands in a sandbox? E.g. grep, awk, sed, etc. Could they work a...

Monitoring the sky - dump1090 to InfluxDB

You may know that i’m very interested in aviation, despite the fact that i had a quite severe case of “being totally afraid of flying” in the past. Or perhap...

Nested netgroups for fun and profit

Imagine you have several hundred systems to manage. The systems are for separate projects and each project has different teams of admins and only assigned ad...

Setting up LDAP for Solaris 11

Some time ago i was asked to provide a walktrough for the configuration of LDAP in Solaris 11. It’s a walkthrough how to set up LDAP name services for Solari...

Telegrafing data to MQTT

On Friday i wrote an article describing how i configured Telegraf to gather monitoring data from my Technische Alternative CMI. In this article i wrote that...

Out of ID

Recently a customer observed on one of their systems, that the number n of databases started quite nicely on a system. However when they tried to start data...

Virtualbox via IPS .p5p

Darren Moffat just pointed to this in his Twitter feed about an package for Solaris that would make installation of this great tool really comfortable. Virtu...

Using the Technische Alternative CMI with Telegraf

My heating system is controlled by an UVR1611 from Technische Alternative as i have to control a wood pellets heater and solar thermal collectors on the roof...

IPMP and additional IP addresses

Recently i had a customer with a problem: The customer configured an IPMP group with a number of additional IPs. They had a number of application servers run...

Common Criteria certification for Oracle Solaris 11.4

Darren Moffat just wrote in the Solaris blog on blog.oracle.com about an important news for Oracle Solaris 11.4: Solaris just got its Common Criteria cerfica...

Integrating Youless energy monitoring devices into Telegraf

I’m playing a lot with Telegraf in recent time in order to get a handle on monitoring an Exadata or the Oracle DB with it. As I don’t have an Exadata at home...

Channel 26

The house i’m living is quite strange in regard of WLAN reception. It’s a house for four families i’m owning. It’s with four floors (including cellar and roo...