Lion's questions

I want to automatically add a DNS CNAME entry using the dnsmasq namespace. Since this seems too complex to be handled by virsh net-edit, my idea is to use virsh net-dumpxml, apply the modifications and re-import the network. While the export works, the import throws an error.

$ virsh net-update --xml network.yml
error: command 'net-update' requires <network> option
error: command 'net-update' requires <command> option
error: command 'net-update' requires <section> option

It seems that net-update doesn't work that way, so I tried it with net-create

$ virsh net-create --file network.yml
error: Failed to create network from network.yml
error: Requested operation is not valid: network is already active as 'mynet.internal'

According to the help, there is no switch to override an existing network.

Since v5.6.0, libvirt added a dnsmasq namespace with the element, which allows to specify options directly to the underlying dnsmasq server. I'd like to create a wildcard DNS entry for my applications with that option. So I used virsh net-edit, changed <network> to <network xmlns:dnsmasq='http://libvirt.org/schemas/network/dnsmasq/1.0'> and added the following options:

  <dnsmasq:options>
    <dnsmasq:option value='cname=boards.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal'/>
    <dnsmasq:option value='cname=*.app.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal'/>
  </dnsmasq:options>

After that, the network was restarted (virsh net-destroy && virsh net-start) and the targeting VM too (virsh destroy && virsh start).

The cname=boards.cnx65-k8s.hobel.internal works perfectly:

$ dig +short boards.cnx65-k8s.hobel.internal @192.168.10.1
cnx65-k8s.hobel.internal.
192.168.10.136

But dig +short x.app.cnx65-k8s.hobel.internal @192.168.10.1 doesn't resolve to any ip address. The generated configuration file /var/lib/libvirt/dnsmasq/hobel.internal.conf contains both cname entries at the end:

strict-order
user=libvirt-dnsmasq
local=/hobel.internal/
domain=hobel.internal
expand-hosts
pid-file=/run/libvirt/network/hobel.internal.pid
except-interface=lo
bind-dynamic
interface=virbr1
dhcp-range=192.168.10.10,192.168.10.254,255.255.255.0
dhcp-no-override
dhcp-authoritative
dhcp-lease-max=245
dhcp-hostsfile=/var/lib/libvirt/dnsmasq/hobel.internal.hostsfile
addn-hosts=/var/lib/libvirt/dnsmasq/hobel.internal.addnhosts
cname=boards.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal
cname=*.app.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal

According to this answer, I added auth-server and interface-name to the options:

  <dnsmasq:options>
    <dnsmasq:option value='cname=boards.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal'/>
    <dnsmasq:option value='cname=*.app.cnx65-k8s.hobel.internal,cnx65-k8s.hobel.internal'/>
    <dnsmasq:option value='auth-server=cnx65-k8s.hobel.internal,virbr1'/>
    <dnsmasq:option value='interface-name=cnx65-k8s.hobel.internal,virbr1'/>
  </dnsmasq:options>

But x.app.cnx65-k8s.hobel.internal is still not resolved:

$ dig x.app.cnx65-k8s.hobel.internal @192.168.10.1

; <<>> DiG 9.16.1-Ubuntu <<>> x.app.cnx65-k8s.hobel.internal @192.168.10.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43624
;; flags: qr rd ad; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;x.app.cnx65-k8s.hobel.internal.        IN      A

;; Query time: 0 msec
;; SERVER: 192.168.10.1#53(192.168.10.1)
;; WHEN: Sat Jul 03 12:14:05 CEST 2021
;; MSG SIZE  rcvd: 59

Why is this not working? Even the official libvirt documentation lists a cname wildcard entry as example:

<dnsmasq:option value="cname=*.foo.example.com,master.example.com"/>

Our developers wants bamboo because of integrations to other Atlassian software and we have regularly problems with this buildserver. Often the buildjobs fail with OutOfMemory exceptions like this:

 java.lang.OutOfMemoryError: unable to create new native thread
        at java.lang.Thread.start0(Native Method)
        at java.lang.Thread.start(Thread.java:717)
        at org.apache.tools.ant.taskdefs.ProcessDestroyer.removeShutdownHook(ProcessDestroyer.java:149)
        at org.apache.tools.ant.taskdefs.ProcessDestroyer.remove(ProcessDestroyer.java:202)
        at org.apache.tools.ant.taskdefs.Execute.execute(Execute.java:481)
        at org.apache.tools.ant.taskdefs.ExecTask.runExecute(ExecTask.java:629)
        at org.apache.tools.ant.taskdefs.ExecTask.runExec(ExecTask.java:670)
        at org.apache.tools.ant.taskdefs.ExecTask.execute(ExecTask.java:496)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
        at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.Task.perform(Task.java:348)
        at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
        at net.sf.antcontrib.logic.IfTask.execute(IfTask.java:197)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.TaskAdapter.execute(TaskAdapter.java:155)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
        at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.Task.perform(Task.java:348)
        at org.apache.tools.ant.Target.execute(Target.java:435)
        at org.apache.tools.ant.Target.performTasks(Target.java:456)
        at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1405)
        at org.apache.tools.ant.helper.SingleCheckExecutor.executeTargets(SingleCheckExecutor.java:38)
        at org.apache.tools.ant.Project.executeTargets(Project.java:1260)
        at org.apache.tools.ant.taskdefs.Ant.execute(Ant.java:441)
        at org.apache.tools.ant.taskdefs.CallTarget.execute(CallTarget.java:105)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
        at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.Task.perform(Task.java:348)
        at org.apache.tools.ant.Target.execute(Target.java:435)
        at org.apache.tools.ant.Target.performTasks(Target.java:456)
        at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1405)
        at org.apache.tools.ant.helper.SingleCheckExecutor.executeTargets(SingleCheckExecutor.java:38)
        at org.apache.tools.ant.Project.executeTargets(Project.java:1260)
        at org.apache.tools.ant.taskdefs.Ant.execute(Ant.java:441)
        at org.apache.tools.ant.taskdefs.CallTarget.execute(CallTarget.java:105)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
        at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.Task.perform(Task.java:348)
        at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
        at net.sf.antcontrib.logic.IfTask.execute(IfTask.java:197)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.TaskAdapter.execute(TaskAdapter.java:155)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
        at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
        at org.apache.tools.ant.Task.perform(Task.java:348)
        at org.apache.tools.ant.Target.execute(Target.java:435)
        at org.apache.tools.ant.Target.performTasks(Target.java:456)
        at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1405)
        at org.apache.tools.ant.Project.executeTarget(Project.java:1376)
        at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
        at org.apache.tools.ant.Project.executeTargets(Project.java:1260)
        at org.apache.tools.ant.Main.runBuild(Main.java:857)
        at org.apache.tools.ant.Main.startAnt(Main.java:236)
        at org.apache.tools.ant.launch.Launcher.run(Launcher.java:287)
        at org.apache.tools.ant.launch.Launcher.main(Launcher.java:113)

The memory is definitely enough. I incrased the bamboo JVM RAM from 512/1024 to 4096MB (both min/max). In the admin UI, there is always at least 50% free. The server itself has 24GB of memory.

It seems that the out of memory error doesn't indicate a lack of memory but lacking OS limits instead. In /etc/security/limits.conf I set the following limits (first to the user bamboo which is used for the jobs, later * for all users):

*      soft   nofile  16384
*      hard   nofile  16384
*      soft   nproc   65535
*      hard   nproc   65535

and also set this in /etc/sysctl.conf:

fs.file-max = 16384

To check that the limits works:

su - bamboo
ulimit -a
core file size          (blocks, -c) unlimited
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 94782
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 16384
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 65535
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

Since bamboo still crashes, I added a shell plan that executes

whoami
ulimit -a

with the following output:

build   07-Feb-2020 11:29:11    bamboo
build   07-Feb-2020 11:29:11    core file size          (blocks, -c) unlimited
build   07-Feb-2020 11:29:11    data seg size           (kbytes, -d) unlimited
build   07-Feb-2020 11:29:11    scheduling priority             (-e) 0
build   07-Feb-2020 11:29:11    file size               (blocks, -f) unlimited
build   07-Feb-2020 11:29:11    pending signals                 (-i) 94782
build   07-Feb-2020 11:29:11    max locked memory       (kbytes, -l) 64
build   07-Feb-2020 11:29:11    max memory size         (kbytes, -m) unlimited
build   07-Feb-2020 11:29:11    open files                      (-n) 4096
build   07-Feb-2020 11:29:11    pipe size            (512 bytes, -p) 8
build   07-Feb-2020 11:29:11    POSIX message queues     (bytes, -q) 819200
build   07-Feb-2020 11:29:11    real-time priority              (-r) 0
build   07-Feb-2020 11:29:11    stack size              (kbytes, -s) 8192
build   07-Feb-2020 11:29:11    cpu time               (seconds, -t) unlimited
build   07-Feb-2020 11:29:11    max user processes              (-u) 94782
build   07-Feb-2020 11:29:11    virtual memory          (kbytes, -v) unlimited
build   07-Feb-2020 11:29:11    file locks                      (-x) unlimited

We can see that e.g. open files ist just set to 4096 instead of 16384 as configured.

What is bamboo doing that he's ignoring those system-wide limits?

I want to change the localisation to en_US.utf8 so that all log messages from applications were displayed in english. This works when I prefix the command with LANG=en_US.utf ./my-command, now every output of ./my-command is english.

localectl seems the right tool to make it permanent, so I tried

[root@cnx65 ~]# localectl set-locale LANG=en_US.utf8

But when now running ./my-command, the output is still in german. According to localectl, we have en_US.utf8 set:

[root@cnx65 ~]# localectl
   System Locale: LANG=en_US.utf8
       VC Keymap: de_alt_UTF-8
      X11 Layout: us

where locale and also the $LANG variable shows still german:

[root@cnx65 ~]# locale
LANG=de_DE.UTF-8
LC_CTYPE="de_DE.UTF-8"
LC_NUMERIC="de_DE.UTF-8"
LC_TIME="de_DE.UTF-8"
LC_COLLATE="de_DE.UTF-8"
LC_MONETARY="de_DE.UTF-8"
LC_MESSAGES="de_DE.UTF-8"
LC_PAPER="de_DE.UTF-8"
LC_NAME="de_DE.UTF-8"
LC_ADDRESS="de_DE.UTF-8"
LC_TELEPHONE="de_DE.UTF-8"
LC_MEASUREMENT="de_DE.UTF-8"
LC_IDENTIFICATION="de_DE.UTF-8"
LC_ALL=
[root@cnx65 ~]# echo $LANG
de_DE.UTF-8

I also verified that the locale exists with localectl -a:

[root@cnx65 ~]# locale -a | grep en_US.utf8
en_US.utf8

Why is this not working? It's not traceable for me. As you can see, all commands ran as root, so there couldn't be a permission issue.

I don't want to just set the LANG environment variable somwhere globally like in /etc/profiles since the server got provisioned by Ansible, so there's no interactive login shell.

For a testing environment, I want to connect multiple VMs using DHCP with their hostnames as DNS entrys. The troubleshooting shows that my DNS/DHCP works. But the VM got registered using ubuntu as hostname instead of my own (k8sm in this example):

root@k8sm:~# ping k8sm -c1
PING k8sm (192.168.2.89) 56(84) bytes of data.
64 bytes from ubuntu.k8s.home (192.168.2.89): icmp_seq=1 ttl=64 time=0.019 ms

Using my k8sm hostname, I didn't get an IP when trying dig +short k8sm.k8s.home @192.168.2.2 (where .2.2 is my DNS server).

Cloudinit user-data

hostname: ${hostname}
fqdn: ${hostname}.k8s.home

Which is called from my Terraform config file here:

data "template_file" "k8sm-cloudinit-data" {
  template = "${file("${path.module}/cloudinit/user-data.cfg")}"
  vars = {
    hostname = "k8sm"
  }
}

According to the logs

root@k8sm:~# grep hostname /var/log/syslog
Jun  6 19:17:09 k8sm systemd-resolved[604]: Using system hostname 'ubuntu'.
Jun  6 19:17:09 k8sm systemd-networkd[581]: Not connected to system bus, not setting hostname.
Jun  6 19:17:09 k8sm systemd-resolved[604]: System hostname changed to 'k8sm'.
Jun  6 19:17:09 k8sm kernel: [    3.526063] systemd[1]: Set hostname to <ubuntu>.
Jun  6 19:17:09 k8sm dbus-daemon[781]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' requested by ':1.0' (uid=100 pid=581 comm="/lib/systemd/systemd-networkd " label="unconfined")
Jun  6 19:17:09 k8sm dbus-daemon[781]: [system] Successfully activated service 'org.freedesktop.hostname1'
Jun  6 19:17:09 k8sm systemd-hostnamed[844]: Changed host name to 'ubuntu'

it seems that my k8sm hostname is applyed, but got overriden by systemd. Why is this happen and what need to be done to set the hostname correctly for DHCP? The target is to reach the machine using k8sm.k8s.home in this example.

hostnamectl shows me the correct hostname in the VM

root@k8sm:~# hostnamectl status
   Static hostname: k8sm.k8s.home
         Icon name: computer-vm
           Chassis: vm
        Machine ID: 001637a6a5e0410f923cb082af1953d2
           Boot ID: 853577fa58844d8e900c107cfb0c1dde
    Virtualization: kvm
  Operating System: Ubuntu 18.04.2 LTS
            Kernel: Linux 4.15.0-50-generic
      Architecture: x86-64

Both host and VM runs 18.04 LTS with KVM 2.11.1.

Another approach I tried

preserve_hostname: true
runcmd:
  - hostnamectl set-hostname k8sm
  - hostnamectl set-hostname k8sm --static

The idea was to skip cloudinits hostname setting with preserve_hostname and set it manually (later), but the result is the same: VM got registered as ubuntu instead of its new hostname.

I've a Windows Server 2012 R2 server which acts as Hyper-V host for multiplice Windows/Linux VMs. Since yesterday the server is offline from one second to another, and will reboot automatically. I found out that this is caused by a bluescreen:

Yesterday this happens three times:

20:57:26

20:15:29

19:57:17

I did a research and find out that this can maybe an issue with an driver, especially the network adapter, and the Large send offload setting. I had it activated, so I disabled it. After that the server runns stable up to now (near 24 hours). Just now the server crashed again.

So it seems like an software issue, but I can't find out what's causing the problem. I haven't install new software or driver in this month, which may be responsible for those problems. Only Windows Updates a few days ago.

All crashes seems the same issue because the bug check string, code and first parameter are the same. Also the driver is equal.

What can I do to find and fix the issue?

I want to create local Client-VMs (Windows 8.1) for our developers. These should connect to our VPN and login on our AD server (Windows Server 2012 R2). I'm using serverside profiles for this so that all settings (e.g. configuration on IDEs like Visual Studio) are stored on the server. We can keep backups of them so that nothing is lost e.g. when the Client-VM crashes because of a disk failture and other possible problems.

At the beginning this is working, but now the synchronisation of the userprofiles isn't working any more. I connect to the VPN at the login screen of the Client-VM and I get logged in without any errors, but e.g. the user-librarys are not synchronized. When I logout, I get an errormessage that my remote profile can't be full synchronized.

In the Logs of the Client I found the following (Bold parts are analogously translated to English because the VM is a German Windows installation, the rest is 1:1 copied from the event-log):

The roaming profile could not be fully updated. Details can be found in the previous events.

We saw that our registry-file is used from other applications or services. The file will be >unloaded now. Applications and services which are using the file will may not work correctly any >more. No user interaction is required

DETAIL - 1 user registry handles leaked from \Registry\User\S-1-5-21-1107009087-2515811915-3103359273->1105_Classes: Process 840 (\Device\HarddiskVolume1\Windows\System32\svchost.exe) has opened key \REGISTRY\USER\S->1-5-21-1107009087-2515811915-3103359273-1105_CLASSES

---

We saw that our registry-file is used from other applications or services. The file will be >unloaded now. Applications and services which are using the file will may not work correctly any >more. No user interaction is required

DETAIL - 2 user registry handles leaked from \Registry\User\S-1-5-21-1107009087-2515811915-3103359273-1105: Process 1296 (\Device\HarddiskVolume1\Windows\System32\spoolsv.exe) has opened key \REGISTRY\USER\S-1-5-21-1107009087-2515811915-3103359273-1105 Process 840 (\Device\HarddiskVolume1\Windows\System32\svchost.exe) has opened key \REGISTRY\USER\S-1-5-21-1107009087-2515811915-3103359273-1105

---

"CoID={2ED062F2-1B38-46D0-BA3E-F4964F86AB0A}: The user "SYSTEM" choosed a connection named "VPN", but the connection was disconnected. The reasoncode which was given by the disconnect was 830.

The sequence corresponds to the eventlog. I think it's very strange that the VPN-Connection was closed before the sync-error of the roaming profile occurs (there are 9 seconds between these two messages). I think that's the problem why the roaming profile can't be synchronized, but it can't explain why it seems that the profile is also not synchronisized on login.

I'm not sure if the log-entrys about the registry have something to do with this issue because it seems that they're about something other (e.g. spoolsv.exe is about the queue for printers) and there is also an info that no action is required (not sure if this is really true).

So my question is: What is the problem here? Why is the sync of roaming profiles not working any more? It's very wired because at the beginning it worked fine. Then I created some GPOs for excluding folders with bulk stuff (e.g. downloads) and since them the problem is there. I also disabled the GPOs (also ALL for testing, including the the default ones) but it's still not working.

And I created a new account in hope that this is a account-specific problem, but nothing changes.

I've to use the userPrincipalName instead of the default sAMAccountName in all applications which are integrated to AD because we've login-names > 20 characters which isn't supported by sAMAccountName. So i changed

gitlab_rails['ldap_uid'] = 'sAMAccountName'

to

gitlab_rails['ldap_uid'] = 'userPrincipalName'

in my /etc/gitlab/gitlab.rb config. That's working, but now I need to enter the login-name AND the domain. Example: A User login is called "Peter". With the sAMAccountName I was able to login by enter "Peter" as Username in Gitlab. But because of the userPrincipalName contains the domain, I now have to enter "[email protected]".

I'm looking to give my users the comfort to enter only the Loginname, without @domain. Something like this so that the User enter "Peter" and git send "[email protected]" to the AD:

 gitlab_rails['ldap_uid'] = '${gitlabUsername}@mydomain.com'

Is this possible?

I've a Windows Server 2012 R2 based Hyper-V host with Windows Server 2012 R2 guest VMs and also Debian 7.6 based VMs. The dynamic RAM is working on Windows guests fine. But on Linux its not and the VM is using the swap instead of getting more RAM from the host!

~#free -m
             total       used       free     shared    buffers     cached
Mem:           490        484          5          0          1          6
-/+ buffers/cache:        476         13
Swap:         1287        106       1181

Some time later:

~# free -m
             total       used       free     shared    buffers     cached
Mem:           490        484          5          0          1          6
-/+ buffers/cache:        476         13
Swap:         1287        110       1177

As you can see, the used swap increased from 106MB to 110MB and the real RAM is still on 490MB. In the Hyper-V settings I configured the following:

RAM on startup: 512MB
Minimal RAM: 512MB
Maximum RAM: 6000MB

I activated the kernel-modules for the Hyper-V integration tools by using http://blogs.msdn.com/b/virtual_pc_guy/archive/2010/10/21/installing-ubuntu-server-10-10-on-hyper-v.aspx So the following kernel-modules are activated:

hv_vmbus
hv_storvsc
hv_netvsc

The output of lsmod say that hv_blkvsc isn't activated, I think that's because there is no GUI on the server.

I've different VMs on a Windows Server 2012 R2 host. The VMs are in a internal subnet. I want to forward traffic to a specific VM by port. For example port 80 goes to 192.168.0.2 and port 443 goes to 192.168.0.3. The reason for this is that we've a linux VM with a caching-server. So port 80 goes to the caching-server which try to get the request from cache. If that's not possible, he fetch the request from the IIS backend on 192.168.0.3. SSL cannot be cached by our caching server and is only used for loggedin-users where caching makes no sense, so we want to forward this directly to the IIS backend.

I tried out Routing and RAS which do exactly what I want. But the problem is: Its VERY slow. My test page took about 10 seconds to load instead 1,5-2s normally. I guess the reason for this is that because of Routing and RAS every single request will be handled by a single HTTP-Connection instead using keep-alive.

So I've two questions:

1. Is it possible to use Routing and RAS for HTTP-Traffic and so I'm only doing something wrong?
2. What can I alternative use for this? The perfect solution would be the possibility to forward single ports like Routing and RAS do. The only alternatives i found are reverse proxys like squid, but they do not work directly unter windows

I want to redirect a SEO-Friendly outgoing link like example.com/out/productxyz with IIS 8.5. So I created a Rewrite-Rule with the Action-Type forward. The target URL has Parameters, e.g. example.com/action.aspx?param1=value&param2=value

The Problem is: When the IIS is saving the rule, the '&' chars from the parameters are converted to their HTML-Values:

<action type="Redirect" url="http://example.com/action.aspx?param1=value&amp;amp;param2=value" redirectType="Found" />

So a '&' is converted to '&'. I took a look in the header and the IIS is exactly redirecting to 'http://example.com/action.aspx?param1=value&param2=value'. This breaks because of the '&' and so I get another side, and not the one which I would get with correct parameters.

I already tried to replace all '&' to '&' in the web.config, but then I got an error in IIS that the config isn't a well-formed xml. So my question: How can I redirect a custom URL to a target URL with URL-Parameters, without broke the parameters?

I'm using IIS 8.5 on Windows Server 2012 R2 to host ASP.NET and also PHP-Applications. Because there are a few different PHP-Apps, I want to restrict the access by using open_basedir. The problem: With the IIS PHP-Manager it's not possible to use a different php.ini file per vHost. So I found a custom solution: After PHP Manager has added the assignment of the php-handler, I modified the executable file as follow:

"C:\Program Files (x86)\PHP\v5.4.26\php-cgi.exe"|-c D:\Sites\my-domain.com

This is working, the vHost is using the php.ini file D:\Sites\my-domain.com\php.ini. But this solution looks a bit dirty to me. Is there a better way of setting a single php.ini file for each vHost?

I using IIS 8.5 with access logs. But the IIS is also logging static content like css/js files and images. This is very useless and will cause unnecessary I/O. So is there a way to disable the access log for individual file types?

I came from linux to windows and in nginx i used something like this to solve the problem:

location ~* ^.+.(jpg|jpeg|gif|png|ico|css|tgz|gz|rar|zip|bz2|doc|xls|exe|pdf|ppt|txt|tar|mid|midi|wav|bmp|rtf|js|ttf)$ {
    access_log off;
    expires max;
}

i'm using nginx with php-fpm and mariadb. Sometimes my pages are loading slow. By checking munin I saw that my average I/O waiting time is very high, up to 8 seconds. In the php-slowlog are mysql-functions listed as reason, for example mysql_query(). I try to tweak the mariadb server (e.g. increase cache, move tmp dir from hdd to a ramdisk). But my I/O gets randomly high.

For example at the beginning of the graph. I thought I fixed the problem, but then the waiting time increases without any visible reason. When I restart mariadb it goes rapidly down (you can see how it goes down at the end, I restarted mariadb here).

I'm not really using much I/O, the peak is about 8MB/s:

Noticeable is that the ratio of Table_locks_immediate to Table_locks_waited is increasing. As i restart mariadb, it was 2.5%. The server is up for ~ 30 minutes now and it had increased to 3.5%. I also noticed that when the server is hanging the number of running threads (Threads_running) is high (up to 30). When this number goes down, the server stops hanging.

My my.cnf:

[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
sync_binlog = 3

user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
#tmpdir     = /tmp
tmpdir      = /var/mysqltmp
lc_messages_dir = /usr/share/mysql
lc_messages = en_US
skip-external-locking
log-bin=/var/mysqltmp/mysql-bin.log
#log=/var/mysqltmp/mysql.log
log-error=/var/mysqltmp/mysql-error.log
log-slow-queries=/var/mysqltmp/mysql-slowquery.log

bind-address        = 127.0.0.1

max_tmp_tables      = 100
max_connections     = 150
connect_timeout     = 5
#wait_timeout            = 600
wait_timeout        = 800
max_allowed_packet  = 16M
thread_cache_size       = 128
#sort_buffer_size        = 4M
sort_buffer_size    = 8M
bulk_insert_buffer_size = 8M
max_heap_table_size     = 128M
tmp_table_size      = 128M
#tmp_table_size          = 64M

# * MyISAM
myisam_recover          = BACKUP
key_buffer_size         = 256M
#open-files-limit   = 2000
table_open_cache    = 1000
myisam_sort_buffer_size = 8M

#concurrent_insert  = 2
#read_buffer_size        = 2M
read_buffer_size    = 4M
#read_rnd_buffer_size    = 1M
read_rnd_buffer_size    = 2M

# * Query Cache Configuration
query_cache_limit       = 256M
query_cache_size        = 256M
# for more write intensive setups, set to DEMAND or OFF
query_cache_type        = ON
#table_cache                    = 400
table_open_cache        = 2000
join_buffer_size        = 4M

# * Logging and Replication
log_warnings        = 2
slow_query_log      = 1
slow_query_log_file = /var/log/mysql/mariadb-slow.log
long_query_time = 1
#log_slow_rate_limit    = 1000
log_slow_verbosity  = query_plan

log_bin         = /var/log/mysql/mariadb-bin
log_bin_index       = /var/log/mysql/mariadb-bin.index
# not fab for performance, but safer
#sync_binlog        = 1
expire_logs_days    = 10
max_binlog_size         = 128M

# * InnoDB
default_storage_engine  = InnoDB
#innodb_log_file_size   = 50M
#innodb_buffer_pool_size    = 256M
innodb_buffer_pool_size = 256M
innodb_log_buffer_size  = 32M
innodb_file_per_table   = 1
innodb_open_files   = 400
innodb_io_capacity  = 400
#innodb_flush_method    = O_DIRECT
innodb_flush_method     = O_DSYNC

[mysqldump]
quick
quote-names
max_allowed_packet  = 16M

[isamchk]
#key_buffer     = 16M
key_buffer             = 32M

!includedir /etc/mysql/conf.d/

I have problems with high I/O on my Debian 7.3 server (up to 7 seconds average I/O wait). I tried to find out what's causing this by using iotop -o. Now I see sonething strange: iotop tells me on the top 'Total DISK WRITE: 32.46M/s'. But in the tasklist I can't see any process writing so much on the disk. The highest are two mysql-processes with 90K/s and 8K/s and a kjournald Process. All three are listed with 99,99% IO. # If I add all the writing speed I come nowhere near to 32MB/s.

Screen of iotop:

What's wrong here? I think 32.46MB/s writing is correct, because at this time my webserver has a high page load time, probably caused of high I/O. But why are the 'big task' which use this much capacity, is not listed in the list below?

Edit: I can also sort it by disk write and i also get strange results like this:

I see sometimes Linux based servers using the swap when it is not necessary. Especially when all of the free ram is used for caching. But now my dedicated server with 16GB RAM begins to swap, although there is enough RAM free:

$ free -m

            total      used     free     shared    buffers     cached
Mem:        16029      10035    5994     0         421         8508
-/+ buffers/cache:     1104     14925
Swap:       19322      3        19319

The server is running a web-server, php and a database which never use all of the 16GB. There should be no need to swap. But Linux still does this. In this case only 3MB but it's the principle.