Latest Server related questions

Score: 0
Anda42 avatar
Disk throughput: Understanding DM writespeed vs SDA
au flag

I am trying to troubleshoot some performance issues.

When i look at my nodeexporter graph, I see numbers i dont understand:

Disk throughput

As I understand, DM-1 is my logical volume, sda is my disk(array).

The write speeds of sda seems within reason for a raid5 of spinny disks, but dm-1 seems like its not possible for that array.

Since the two graphs correlate, is it just an issue of misrepresen ...

Score: 1
Stanley avatar
Reverse Proxy config from Nginx to Ubuntu Apache2
tj flag

The following are 2 corresponding sets of config statements. The first one is for Nginx and the second one for Apache2 servers.

The Ubuntu Apache2 config code is modelled after the Nginx code to provide the same functionality.

The two config paragraphs work the same except that the Nginx code paragraph has an extra "set $args" statement.

# Nginx Sample

server {
        listen       80;             
     ...
Score: 1
Raymond Pang avatar
How to spin up AWS computing resource on demand within 10 seconds delay apart from using Lambda?
co flag

Upon user request, my application has to run a CPU heavy application that requires 6 CPU processes. To reduce latency and speed up development, I choose a monolith approach. Therefore, I simply put everything in an 8 cores CPU instead of using event-driven tools like Lambda.

To save server cost, I want my AWS EC2 instance to start only when the end user click "start" on the browser. To maintain a ...

Score: 1
Thomas Campbell avatar
Ubuntu 22.04.1 LTS (Jammy Jellyfish) Hangs On Reboot (sometimes)
tm flag

I have an Intel NUC NUC8I7HNK which I have installed Ubuntu on. If I reboot the system and then reboot it again everything is fine. Reboots without problem.

However, if I let the system sit for a few days (I don't have an exact time period) and then I try to reboot it will hang.

This could be related to grub as I believe before I made the following changes it may not have had this reboot problem:

Score: 2
John Skiles Skinner avatar
What is the purpose of version dates in AWS policy documents
cr flag

AWS policies contain a date version. What is its purpose? In this example a bucket policy and a user policy both contain "Version": "2012-10-17" in the JSON. I don't see the purpose of the date explained in the docs.

I want to add statements from this AWS documentation show with the date 2012-10-17 to an s3 bucket policy that has existing statements with a different version date, 2008-10-17. Is th ...

Score: 0
catFly avatar
Postfix-How to filter all lines with header_checks?
ly flag

Header_checks filter headers line by line. I want to use !/Message-Id/ to match the email without header Message-Id,and discard it. How to solve it? The code below not effects.

!/Message-ID:/m DISCARD

or

!/*Message-ID:*/m DISCARD

The first one will discard when headers having Message-ID. The last one not discard any way.

Score: 0
Divija Gogineni avatar
How to mount a used ssd to a linux server
nl flag

I want to use my secondary ssd onto my server (the ssd was earlier was used on the same server before the OS on the server was reinstalled). How to mount the ssd so that I can use the old data?

Score: 1
Larry avatar
How are Linux ACLs different for files versus sockets
ru flag

With umask 0022, using default ACL entries default:user::rwx, default:group::rwx, default:mask::rwx and default:other::rwx for a directory, files created with touch (e.g.) have a mask of rw, and sockets created with nc -lU (e.g.) have a mask of r-x — why?

Score: 1
Lázár Zsolt avatar
Rsync makes the destination folder unwritable before copying files to it (and then of course it fails with Permission Denied)
in flag

I want to use rsync to deploy a project from my dev machine (Windows 11, CygWin) to a remote server (Ubuntu) through SSH. I've made sure that my SSH user has full write access to the destination folder by running the commands below:

root# mkdir /opt/my-project
root# chmod +rwx /opt/my-project
root# cwown -R ubuntu /opt/my-project
ubuntu$ touch /opt/my-project/test && rm /opt/my-project   #  ...
Score: 0
Carlo Mencarelli avatar
No Route To Host With StrongSwan Tunnel Interface
in flag

I'm using Ubuntu 20.04 with Strongswan 5.8.2. Configured using the Route-Based VPN instructions.

The site-to-site tunnel establishes and is stable, however, I can't route traffic over it. When I try to ping, ssh, curl I get a "No route to host" error. I can see the traffic in a TCPDump over my VTI interface.

I created my tunnel using the above instructions:

ip tunnel add vti0 local 10.50.1.25 remote 100 ...
Score: 0
A X avatar
Envoy proxy random load balancing option is not random
my flag
A X

We are using the below Envoy load balancing YAML file. It is working but it is NOT randomly distributing requests across nodes 1, 2, and 3. In our use case, we have high load coming from a single source IP address (customer server). We want to distribute the traffic across the nodes like so:

Request 1 -> Node 1 Request 2 -> Node 2 Request 3 -> Node 3 Request 4 -> Node 1

However, this  ...

Score: 1
LegionNexus avatar
How to dynamically assign an internal DNS server to an internal client that receives dynamic IP information from an external DHCP server?
ee flag

My question title sums up everything, what I am trying to archive here is – when an internal client (laptop in the network diagram picture) joins the internal L3 switch on the Lab side, it should dynamically receive the internal DNS server IP instead of external university DNS server IP. I can modify the Lab side network and add any necessary network device, only catch is all devices are need to be dy ...

Score: 0
M-BNCH avatar
Native memory allocation failed to map bytes for committing reserved memory
sd flag

I have multi spring boot applications running on the same server, each one in a separate Tomcat. One of those services crasher because of insufficient memory.

# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 518520832 bytes for committing reserved memory.
# Possible reasons:
#   The system is out of physical RAM or swap spa ...
Score: 0
Iowa avatar
Determine the number of connections initiated to the database
es flag

We have a 3 tier architecture application wherein there is a recent surge in the number of inactive sessions in the database. We are using oracle database and weblogic application server. We have 'n' number of processes running in the server, which connect to the database for reads and writes.

After spending lot of ways to narrow down the cause of the connection leaks, I stumbled upon the ss comm ...

Score: 0
Tom avatar
Too many connections in Exim4
bf flag
Tom

Some users have complained that they are unable to send emails to us. In their logs appears the message "Too many concurrent SMTP connections; please try again later.".

Checking our logs, we noticed several messages with the error below:

2022-10-18 11:01:40 Connection from [X.X.X.X] refused: too many connections
2022-10-18 11:01:40 Connection from [X.X.X.X] refused: too many connections
2022-10-18 11: ...
Score: 0
Klagor Mundavi avatar
QUuestion regarding a Ubuntu Canonical Arm server
ar flag

I wanted to ask about an Ubuntu Canonical Arm64 server i got. It has 200GB storage, 24GB or ram and 4v cpus running Ubuntu Canonical Arm64.

I wonder how this server would compare to a Intel® Xeon E3-1230 RAM with 16 GB ram ?

Score: 0
MikeSchem avatar
Install HA Kube
sa flag

I've tried following various different guides on installing HA kube and I cant get anything to work.

My basic setup is to have 3 master nodes with Keepalived creating a virtual IP (10.10.20.30) and keepalived to send the traffic to the kubelet that is up. I run this script on one fresh ubuntu install and I'm planning on using the provided master join command to join more masters.

I'm under the impr ...

Score: 1
jose cervantes avatar
Is it possible to clear the cache of a specific url with NGINX?
pe flag

0

I am using NGINX as a reverse server, but I have a problem when making changes to a page of my website, the changes are not seen until I clean the entire NGINX cache, causing it to clean my entire site and not just in the URL where I am working.

So I would like to know if it is possible to only clear the cache of a specific URL.

I have configured the dynamic content part but the page load exceeds 600 ...

Score: 0
user2104891 avatar
How do you prove RFC 791 - Internet Protocol
br flag

We are being asked to prove we are using RFC 791 (Internet Protocol) within our network. How does one prove such a thing via documentation if there is no such document from the vendor stating as much....such as Cisco who built their entire company on this protocol....Specifically for the Cisco 9000 series switches...but also every single network card in the entire facility.

Score: 0
Santosh Baruah avatar
nginx: [warn] server name has suspicious symbols with long domain redirect
co flag

What is the best way in Nginx to redirect two Long domains URLS, I would like to configure a redirect between two domains like this:

I'm sure this has been asked before, but I can't find a solution that works.

original link:

https://qwerty.test.com/education/7/abc-science

New link

https://www.test.com/education/7/abc-science

I have tried this :

server {
    listen 80;
    listen 443 ssl;
    serv ...
Score: 0
ChimneyImp avatar
Can I use Zookeeper 3.7.1 with Solr 7.7.3?
cn flag

Each version of Solr ships with a version of Zookeeper. Solr's docs say that you should upgrade Zookeeper if you upgrade Solr, but can you upgrade Zookeeper to a later version that is shipped with Solr without upgrading Solr? The specific version I'm looking at is having Solr 7.7.3 use external Zookeeper 3.7.1 rather than the ZK 3.4 it comes with, since 3.4 is EOL and 3.7 is supported. I searched for a ...

Score: 0
HAVM avatar
yum error | Centos 5
li flag

Hi guys, I am trying to install "Development Tools"... Why? I need to have installed gcc in Centos 5, (yes I know it is old!).

But When I try to install with "yum",


Install 62 Package(s)

Upgrade 2 Package(s)

Total size: 102 M Is this ok [y/N]: y

Downloading Packages:

Running rpm_check_debug

Running Transaction Test

Finished Transaction Test


Once the installation finishes, I see "Finish ...

Score: 0
B P avatar
Share files via a shared disc across multiple VM's running Ubuntu 18?
mp flag
B P

I am trying to share a single disk across multiple VM's (Ubuntu 18). The VM's are hosted in Azure and the disk is an Azure Managed Disk. I've attached the disk to both VM's and have mounted them. I can see the partition on each, as well as the test file I've created, test.txt. However, updates to the contents of the txt file while SSH'ed into VM1 are not reflected in VM22. Instead, the VM2 shows the pri ...

Score: 0
Klagor Mundavi avatar
Ubuntu apache2 access
ar flag

I installed Canonical-Ubuntu-22.04-aarch64 on oracle Cloud and installed apache2 on it but i cant access it on the public ip and i wonder if anyone can help me out here.

In the Default Security List for vcn i opened port 80 but the server returns ERR_CONNECTION_TIMED_OUT when trying to access it

No 0.0.0.0/0 TCP All 80 TCP traffic for ports: 80

Score: 1
Valerica avatar
Malformed BASE64 value in vmail_ssl.map.db
cn flag

I'm using postfix in Ubuntu 20.04.5 . Here's my vmail_ssl.map file, with domain names redacted:

mail.domain.org /etc/letsencrypt/live/mail.domain.org/privkey.pem /etc/letsencrypt/live/mail.domain.org/fullchain.pem
mail.domain.net /etc/letsencrypt/live/mail.domain.net/privkey.pem /etc/letsencrypt/live/mail.domain.net/fullchain.pem

Each time I use postmap to create vmail_ssl.map.db, it truncates the .ne ...

Score: 0
Stephen Okita avatar
Infinite Redirect after Certbot https configuration
tn flag

Hey so I wanted to add https

I started with a simple nginx config of

worker_processes    1;
events {
    worker_connections  1024;
}

http {
    server {
        listen 80;
        server_name www.danielokita.com;
        location / {
            proxy_pass http://172.104.177.135:3333/;
        }
    }
}

Ran certbot --nginx

Now have

worker_processes    1;
events {
            worker_connections  102 ...
Score: 0
kromaak avatar
How to stop tomcat from compiling jsp for single page app
bn flag

We have a server with tomcat 9 running on RedHat linux, and a vendor provided dynamic content management system that builds jsp pages to show news article types of content based on a query string parameter. So kind of a typical single page app, where the URL would look like https://domain/path/index.jsp?id=654321

And on the page we supply the underlying java code with the dynamic component that  ...

Score: 0
Michaël van de Weerd avatar
SSL stapling and variable SSL certificates in NGINX
id flag

I have several domains, all of which are served by the same NGINX instance. I am trying to setup a generic server configuration for HTTPS, such that every domain uses its own certificate and has SSL stapling enabled. These settings as defined in default.conf are as follows:

server {
    listen 443 default_server ssl;

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-E ...
Score: 0
Arsalan avatar
Tunnel two server's traffic to access Internet
ae flag

enter image description here

Is there a solution to config VPN access between two hop's (server's)? I want to use openVPN in my Internal server that has no Internet access Thanks

Score: 0
Cavalcade avatar
Singularity vs. Podman for HPC workloads?
bs flag

Singularity is said to work well for HPC workloads. RedHat is making an effort to make Podman more usable for HPC, e.g. it (and I presume this is with their ubi8 image) is said to work with MPI. That's about all I know. Does anyone have an opinion on which of these tools would work best for HPC users?

One think I like about Singularity is that it is relatively easy for users to mount file systems ...

The Stunning Power of Questions

Much of an executive’s workday is spent asking others for information—requesting status updates from a team leader, for example, or questioning a counterpart in a tense negotiation. Yet unlike professionals such as litigators, journalists, and doctors, who are taught how to ask questions as an essential part of their training, few executives think of questioning as a skill that can be honed—or consider how their own answers to questions could make conversations more productive.

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