# Linux # SSL Linux # Configure local https on ubuntu

T0 set up a local HTTPS server on Ubuntu, use a tool like

`mkcert` for simplicity or `openssl` for more control, and then configure your web server (e.g., Apache) to use the generated certificates. The recommended method is to install and use `mkcert`, which generates a trusted, local Certificate Authority (CA) to create self-signed certificates for `localhost` or custom hostnames without browser warnings. Alternatively, you can generate a self-signed certificate using `openssl`, which requires more manual steps to create the key, certificate, and to trust it in your browser.

**Method 1: Using `mkcert` (Recommended)**

This video demonstrates how to set up HTTPS with mkcert and enable HTTPS for localhost:

[

Unconventional Coding

YouTube • 31 Dec 2022

](https://www.youtube.com/watch?v=sDAX1uQzM8Y&t=98)

1. **Install `mkcert`**: Install the tool to manage local certificate authorities and certificates. - `sudo apt install mkcert` 2. **Install the local CA**: Run `mkcert` to install a local CA that your system will trust. - `mkcert -install` 3. **Create a certificate**: Generate a certificate and key for your local site (e.g., `localhost`) or domain. Point to note here in case of domain, ip address should be mapped to it before this command. - `mkcert localhost 127.0.0.1` - `sudo mkcert drupalwithdata.offline.com` **Configure your server**: Configure your specific application or web server to use the generated `localhost.pem` (certificate) and `localhost-key.pem` (key) files.

**Method 2: Using** [**openssl**](https://www.google.com/search?q=openssl&client=ubuntu-sn&hs=Apb&sca_esv=fdcf620e6fdd6b42&channel=fs&sxsrf=AE3TifMs3NUy9xJXuC_WremxvKGCiYWu5w%3A1763436008369&ei=6OUbaeOZFpmK4-EPgKT-0Aw&ved=2ahUKEwjciuuK3_qQAxXnn2MGHQvCCysQgK4QegQIBRAA&uact=5&oq=how+to+make+https+working+local+machine+server+in+ubuntu&gs_lp=Egxnd3Mtd2l6LXNlcnAiOGhvdyB0byBtYWtlIGh0dHBzIHdvcmtpbmcgbG9jYWwgbWFjaGluZSBzZXJ2ZXIgaW4gdWJ1bnR1MgUQIRigATIFECEYoAEyBRAhGJ8FMgUQIRifBUiDFVCQBVipEnAAeAKQAQCYAb0DoAH6EKoBCTAuMy4zLjAuMrgBA8gBAPgBAZgCCaACzxLCAgQQABhHmAMAiAYBkAYIkgcJMS4wLjUuMS4yoAeFPbIHBzItNS4xLjK4B7ISwgcFMy02LjPIB4kB&sclient=gws-wiz-serp&mstk=AUtExfAKClluadKAjH33L9mMJ_sw0VdX8Y5e8Ru52psIXP50rdxYT2BlcgevvZLj8elFGkTECLTUx3Un7qBFeVoef6Z_SOmPlYwzvICaEKZ_Uam86pUZ7l3RKBeiuSFJqHVm0dXOzK110UNDjaPY3uOWp0IF4vMdgjs0cjXVAMhGrrjP-DOSY5R8Gb2rv38XH-i7cvKci-tenMPUjjaASBmE5vGRQz6LIeCwbcNLaxqCOj1FI7Y3U84XRHJpXW1KrPrG33pgNCd9vFY0FnoH3AW_Y4TO&csui=3)

1. **Install `openssl`**: Ensure `openssl` is installed. It is usually pre-installed on Ubuntu. 2. **Generate a private key and a certificate signing request (CSR)**: - `openssl req -new -newkey rsa:2048 -nodes -keyout localhost.key -out localhost.csr` 3. **Generate the self-signed certificate**: Use the CSR and private key to create the certificate. - `openssl x509 -req -days 365 -in localhost.csr -signkey localhost.key -out localhost.crt` 4. **Configure your web server**: - **For Apache**: - Enable the SSL module: `sudo a2enmod ssl`. - Configure your site's virtual host to point to your certificate (`localhost.crt`) and private key (`localhost.key`) files. - Restart Apache: `sudo systemctl restart apache2`. - **For other servers**: Configure your server's settings to use the `.crt` and `.key` files. 5. **Trust the certificate**: - This is an optional but recommended step to avoid browser warnings. - Install certificate utilities: `sudo apt-get install libnss3-tools`. - Import and trust the certificate into the browser's database (using `pk12util` for Firefox or `certutil` for other applications).

Final steps for both methods

- After generating the certificates and configuring your server, you may still see a browser warning because the certificate is "self-signed" and not issued by a public Certificate Authority. - You will need to accept the security risk to proceed to your local serve # install OpenSSL locally on Ubuntu

To install OpenSSL locally on Ubuntu, you can

compile and install it from source by first installing build tools, then downloading and extracting the OpenSSL source code, and finally running the [config](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=config&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAC), [make](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=make&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAD), and [make install](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=make+install&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAE) commands with the appropriate prefix and flags. For the simplest local installation, download the source, change to the directory, and use [./config --prefix=~~/openssl --openssldir=~~/openssl](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=.%2Fconfig+--prefix%3D%2Fopenssl+--openssldir%3D%2Fopenssl&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAF), followed by [make](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=make&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAG) and [make install](https://www.google.com/search?client=ubuntu-sn&channel=fs&q=make+install&mstk=AUtExfAjQ3yPV6W7WUvN1VS1YZ9pBgUtBJ4QdQKDpIZ5juCvIk2wvERVtHMHcsG7sW_Hs6PlHQDur1gJCpdmD0A6d7-mxwgga1BBPLCiJCP_WY_V_2NMrAWg5BIFnW-7NDB5DfAUaNZQqAXv71YbpKEid0pdVdtxjQBOMlH7pyEwey68lTqabptCWIixVMfn8xDXDJqUSsxDnktUl0HxFZ2CK_8HoFWfqJkY50_E-cv3b0sOZuIoeTHVfpoYXU5cz9ESn4GbuQ-lLKsaZoru0jJ2skEe&csui=3&ved=2ahUKEwiwqZzJ3_qQAxXZSmwGHUH1NmMQgK4QegQIARAH), then update your `~/.bash_profile` with the correct `PATH` and `LD_LIBRARY_PATH`.

Method 1: Install from source to a local directory

This method installs a specific version of OpenSSL to a custom directory, like `~/openssl`, so it doesn't interfere with the system-installed version.

bash

``` # Install build tools sudo apt update sudo apt install build-essential zlib1g-dev # Create a working directory and download OpenSSL source cd /usr/local/src/ wget https://www.openssl.org/source/openssl-1.1.1k.tar.gz tar -xf openssl-1.1.1k.tar.gz cd openssl-1.1.1k # Configure and build (using --prefix to specify local install) ./config --prefix=~/openssl --openssldir=~/openssl make # Install to the local directory make install ```

Method 2: Update your environment variables

After installing from source, you must tell your shell where to find the new binaries and libraries.

1. **Edit the bash profile**:

bash

2. ``` nano ~/.bash_profile ``` 3. **Add the following lines at the end of the file** (adjusting `username` if necessary):

bash

4. ``` export PATH=$HOME/openssl/bin:$PATH export LD_LIBRARY_PATH=$HOME/openssl/lib:$LD_LIBRARY_PATH export LDFLAGS="-L $HOME/openssl/lib -Wl,-rpath,$HOME/openssl/lib" ``` 5. **Save and close** the file, then reload your profile:

bash

``` source ~/.bash_profile ```

Method 3: Verify the installation

1. **Check the version** to ensure you are using the new installation:

bash

2. ``` openssl version ``` This should output the version you installed (e.g., `OpenSSL 1.1.1k 25 Mar 2025`). **Verify the path** to confirm it's the local one:bash ``` which openssl ``` This should point to `~/openssl/bin/openssl` # MULTIVERSIONS ON UBUNTU BOX sudo apt install apache2 libapache2-mod-fastcgi sudo apt-get install mysql-server sudo mysql\_secure\_installation sudo apt install software-properties-common sudo add-apt-repository ppa:ondrej/php sudo apt update Use this command to install different versions of php just changing the string 7.1 to the required version sudo apt install php7.1 php7.1-fpm libapache2-mod-php7.1 NOW ALL SET LAMP is installed and working Now while u will require to change the php version This command will change the php version on system sudo update-alternatives --config php Disable all version apached modules of php installed, just replace the 7.4 in below command sudo a2dismod php7.4 Enable the version u need to use with apache, just replace the 8.0 in below command sudo a2enmod php8.0 Restart the apache sudo service apache2 restart # kernel tuning/troubleshooting

Kernel tuning/troubleshooting involves adjusting operating system (OS) parameters for performance/stability (tuning) or fixing crashes/issues (troubleshooting), often using tools like `sysctl`, `ulimit`, `make menuconfig` (Linux), or boot options/diagnostics (Mac/Linux), focusing on memory, filesystems, I/O, and software conflicts to match workloads, requiring careful baselining and testing to avoid instability.

Kernel Tuning (Linux Focus)

- **Goal:** Optimize performance (speed, resource use) for specific workloads (e.g., databases, web servers). - **Key Areas:** - **[fs (Filesystem)](https://www.google.com/search?q=fs+%28Filesystem%29&oq=kernel+tuning%2Ftroubleshooting&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRigATIHCAMQIRigATIHCAQQIRigATIHCAUQIRiPAtIBBzcwN2owajeoAgCwAgA&sourceid=chrome&ie=UTF-8&mstk=AUtExfDkCAWWifP2YSKeN9WF7oTwE4I3r6YUnc79ZZayD4Dp2Q1_DtVkgaJF1RuSKZ6mmZmmoTHG92ujhHwuv8BnFtoJX8EKLwalGtQgwIeGrOpXY93X5HSl3sUk-8pzgV_J4aanf9ZF7801b2CmL-9N7bz-wEs3iCvqSOwMDFSxyOgS9e8kvJdpP3Z7e5_ciIlsr9MCGUiQdpimObmqcPfu9KSvQMUFdFePcoSZOXR3i1D425Ks1LEyk54VVPHn-rmAMVO1t1WxlT1xxMeDRpzZeCAB&csui=3&ved=2ahUKEwjgv-Ps-7WRAxWAe2wGHVIgIgcQgK4QegQIAxAD):** Too many open files (`ulimit -n`), I/O schedulers. - **[vm (Virtual Memory)](https://www.google.com/search?q=vm+%28Virtual+Memory%29&oq=kernel+tuning%2Ftroubleshooting&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRigATIHCAMQIRigATIHCAQQIRigATIHCAUQIRiPAtIBBzcwN2owajeoAgCwAgA&sourceid=chrome&ie=UTF-8&mstk=AUtExfDkCAWWifP2YSKeN9WF7oTwE4I3r6YUnc79ZZayD4Dp2Q1_DtVkgaJF1RuSKZ6mmZmmoTHG92ujhHwuv8BnFtoJX8EKLwalGtQgwIeGrOpXY93X5HSl3sUk-8pzgV_J4aanf9ZF7801b2CmL-9N7bz-wEs3iCvqSOwMDFSxyOgS9e8kvJdpP3Z7e5_ciIlsr9MCGUiQdpimObmqcPfu9KSvQMUFdFePcoSZOXR3i1D425Ks1LEyk54VVPHn-rmAMVO1t1WxlT1xxMeDRpzZeCAB&csui=3&ved=2ahUKEwjgv-Ps-7WRAxWAe2wGHVIgIgcQgK4QegQIAxAF):** Swappiness (`vm.swappiness`), dirty ratios, memory management. - **Networking:** TCP/IP settings, buffer sizes. - **Tools:** `sysctl`, `/etc/sysctl.conf`, `make menuconfig` (for compiling custom kernels), `tuned` (profiles).

Kernel Troubleshooting

- **Common Issues:** [Kernel Panic](https://www.google.com/search?q=Kernel+Panic&oq=kernel+tuning%2Ftroubleshooting&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRigATIHCAMQIRigATIHCAQQIRigATIHCAUQIRiPAtIBBzcwN2owajeoAgCwAgA&sourceid=chrome&ie=UTF-8&mstk=AUtExfDkCAWWifP2YSKeN9WF7oTwE4I3r6YUnc79ZZayD4Dp2Q1_DtVkgaJF1RuSKZ6mmZmmoTHG92ujhHwuv8BnFtoJX8EKLwalGtQgwIeGrOpXY93X5HSl3sUk-8pzgV_J4aanf9ZF7801b2CmL-9N7bz-wEs3iCvqSOwMDFSxyOgS9e8kvJdpP3Z7e5_ciIlsr9MCGUiQdpimObmqcPfu9KSvQMUFdFePcoSZOXR3i1D425Ks1LEyk54VVPHn-rmAMVO1t1WxlT1xxMeDRpzZeCAB&csui=3&ved=2ahUKEwjgv-Ps-7WRAxWAe2wGHVIgIgcQgK4QegQIBRAB) (system crash), slow performance, device failures. - **Steps:** 1. **Identify Cause:** Check logs (`dmesg`, `/var/log/`), review crash reports (Mac), use `journalctl` (Linux). 2. **Isolate:** Boot in Safe Mode (Mac), use a known good/rescue kernel (Linux), disconnect hardware, remove recent software/drivers. 3. **Check Hardware:** Run diagnostics (Apple Diagnostics), check RAM. 4. **Software Conflicts:** Look for recently installed or updated apps/drivers causing issues.

Best Practices

- **Baseline:** Measure performance *before* changes. - **Change Incrementally:** Adjust one or a few parameters at a time. - **Document:** Keep records of all changes and their effects. - **Test Thoroughly:** Verify stability and performance after each change.

Jupyter Notebook Kernel Issues (Related but Different)

- If "kernel" means the Jupyter backend: Restart, update packages (Jupyter, Anaconda), check code for errors, monitor memory. # filesystems tuning

File system tuning optimizes storage performance by adjusting settings like block size, caching, journaling, and I/O methods (sync/async) to match workloads, improving speed, throughput, and resource use for specific tasks, crucial for servers running databases or virtual machines. Key techniques involve optimizing disk hardware, tuning buffer sizes (like `numfsbufs`), leveraging read-ahead/write-behind, using Direct I/O, and applying system profiles via tools like `tuned-adm` for Linux, all aiming to reduce bottlenecks and enhance efficiency.

Core Concepts & Parameters

- **I/O Operations:** Tuning reads/writes, utilizing asynchronous I/O (AIO) to prevent application blocking, and optimizing read-ahead for sequential access. - **Block Size:** Affects data efficiency; larger blocks can speed up large file transfers, while smaller ones suit many small files. - **Caching & Buffers:** Increasing file system buffers (`numfsbufs`) can help with heavy I/O; faster RAM disks for `/tmp` also boost performance. - **Journaling:** Balancing the performance impact of logging changes for data integrity (e.g., using `commit` options). - **File System Type:** Different file systems (Ext4, XFS, NTFS) have unique strengths; tuning depends on the chosen one.

Key Tuning Techniques

- **Hardware Optimization:** Ensure disk controllers use fast DMA modes. - **Read-Ahead/Write-Behind:** Boost sequential read/write performance by pre-fetching/delaying writes. - **Direct I/O (DIO):** Bypasses the kernel's file cache to reduce CPU load and data copies for specific applications. - **[Tuning Profiles](https://www.google.com/search?q=Tuning+Profiles&oq=filesystems+tuning&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIJCAEQIRgKGKABMgkIAhAhGAoYoAEyCQgDECEYChigAdIBCDEwMDZqMGo3qAIAsAIA&sourceid=chrome&ie=UTF-8&mstk=AUtExfB3O1nSYHBoMsTk8NWWWKzadhQpv7QRxBXCZynmQjNfzvsBQ9SFkAAMUBfnq3xs4bOf9oBjdlOnH7-HONvsuCcaeoeC8XNTn17-h0YXE_iuT8csuUw0nHg_yr8K7dxFdiOhbHzwL68Oukh-VmEp98IlCaB0Dh-OGmFy-_Ydf2I7hHUquQDADEhcX9bm6jTGwsGsIl_lJa3JH2UjjNlW6vlfhG8l_XCl4w54ecK9Z5Zbl86AQ1WvoSMPPRpTObQz5sk_zQSmksVlj4wb_2_0PAOU&csui=3&ved=2ahUKEwiJh7fD_LWRAxV0UGwGHT4HCRsQgK4QegQIBRAE) (Linux):** Use `tuned-adm` to apply profiles (e.g., `throughput-performance`, `virtual-guest`) for workload-specific settings. - **Application-Level:** Design apps to gather large data chunks and write them sequentially.

How to Approach Tuning

1. **Monitor:** Identify bottlenecks using tools like `vmstat -v` or `iostat`. 2. **Select:** Choose parameters relevant to your workload (e.g., database needs high I/O, web server needs low latency). 3. **Apply:** Use commands like `mkfs` (for creation), mount options, or `tuned-adm` to change settings. 4. **Test:** Verify improvements with performance benchmarks.