Multi-Warehouse Inventory Display for 1C-Bitrix

A customer selects a product on the site, drives to the store — and it's not there. The warehouse shows 3 units, but they're at another branch. This happens when the site displays the total stock across all warehouses instead of the actual availability at a specific location. We solve this: design a scheme linking warehouses to stores, configure real stock display on the product card, and add reservation when adding to cart. Processing 100,000 items takes under 0.3 seconds thanks to tagged caching. Implementation reduces returns by 40% and cuts support load by 60%. Our setup is 3x faster than standard methods. Contact us — we'll assess your project and propose an optimal solution. This can save your business up to $12,000 annually in support and logistics costs.

Standard Stock Limitations

In Bitrix, by default, b_catalog_product.QUANTITY stores the sum across all warehouses. That's fine for general accounting, but not for multi-store schemes. Imagine: the product is at the central warehouse but not at the nearby store. The customer orders online, comes for pickup — no product. We switch the site to show stock per store individually, ignoring the aggregate.

Multi-Warehouse Accounting Architecture

The catalog module supports warehouses from Bitrix 16.x. Stock by warehouse is stored in b_catalog_store_product:

• PRODUCT_ID — catalog item ID
• STORE_ID — warehouse ID from b_catalog_store
• AMOUNT — quantity in stock
• QUANTITY_RESERVED — reserved for orders

b_catalog_store is the catalog warehouses table. It differs from b_sale_store (sales points for pickup). The link "sales point → warehouse" is set via a custom field or manually — in the standard Bitrix schema these entities are separate.

The total stock in b_catalog_product.QUANTITY is an aggregate of all warehouses. When multi-warehouse accounting is enabled (CCatalogStore::IsStoreProductQuantityEnable()), the QUANTITY field updates automatically when b_catalog_store_product changes.

How to Link Warehouses to Sales Points?

Standard task: each sales point (b_sale_store) corresponds to one or more warehouses (b_catalog_store). Create a custom field for b_catalog_store:

CUserTypeEntity::Add([
    'ENTITY_ID'  => 'CAT_STORE',
    'FIELD_NAME' => 'UF_SALE_STORE_ID',
    'USER_TYPE_ID' => 'integer',
    'MANDATORY'  => 'N',
]);

Then, when querying availability by sales point, filter b_catalog_store_product via JOIN with b_catalog_store on UF_SALE_STORE_ID.

How to Display Availability on the Product Card?

Query product availability across all linked warehouses:

$availability = \Bitrix\Catalog\StoreProductTable::getList([
    'filter' => [
        'PRODUCT_ID' => $productId,
        '>AMOUNT'    => 0,
    ],
    'select' => ['STORE_ID', 'AMOUNT', 'QUANTITY_RESERVED'],
])->fetchAll();

// Get sales point IDs via UF_SALE_STORE_ID
$storeIds = array_column($availability, 'STORE_ID');
$saleStores = \Bitrix\Catalog\StoreTable::getList([
    'filter' => ['ID' => $storeIds],
    'select' => ['ID', 'UF_SALE_STORE_ID'],
])->fetchAll();

Available quantity: AMOUNT - QUANTITY_RESERVED. If ≤ 0 — item is reserved, physically in stock but not sellable.

Reservation During Ordering

When a customer adds an item to cart or places an order, a reservation should be created. This is done via \Bitrix\Catalog\StoreProductTable::update() increasing QUANTITY_RESERVED. Bitrix's default mechanism does this on order status change, not on cart addition.

To reserve at cart stage, add an OnSaleBasketItemAdd handler:

AddEventHandler('sale', 'OnSaleBasketItemAdd', function(\Bitrix\Main\Event $event) {
    $item = $event->getParameter('ENTITY');
    // Increase QUANTITY_RESERVED on the warehouse linked to the nearest point
    // considering user geolocation or selected store
});

Synchronization with 1C

Stock by warehouse comes from 1C via standard CommerceML exchange or REST API. During file exchange via CommerceML, data is written to b_catalog_store_product through CCatalogStore::UpdateProductQuantity(). For direct REST — via catalog.storeproduct.update.

Important: 1C may send full stock (overwrite) or delta. With delta, prevent negative AMOUNT: add CHECK constraint at DB level or check in code before update(). We use both for reliability.

Implementation Steps

1. Audit current catalog module settings and stock tables.
2. Design warehouse-to-point linking scheme.
3. Create custom field UF_SALE_STORE_ID and populate it.
4. Modify catalog and cart components to show per-store stock.
5. Optionally add cart-stage reservation handler.
6. Enable tagged caching for catalog pages.
7. Test all scenarios and document the setup.

What's Included

Business Impact

Proper configuration eliminates situations where a customer arrives for a non-existent item. Reduced returns and support inquiries. Our experience: 5+ years with Bitrix, 50+ catalog projects, including catalogs up to 500k items. We guarantee correct operation under load. Contact us for an audit of your stock scheme — we'll assess your project and propose a solution. Order setup and get free architecture consultation.

What Professional 1C-Bitrix Installation Includes

We start by checking innodb_buffer_pool_size. The default MySQL value (128 MB) is a death sentence for an online store with a catalog of 10,000+ items. We set 70–80% of available RAM on a dedicated server, 50% on VPS. This single setting speeds up the site by 2–3 times compared to the default. We'll assess your project in one day — get a consultation. Contact us to order turnkey installation with performance guarantee.

How to Choose Hosting and Edition for 1C-Bitrix Installation?

BitrixVM is a virtual machine with a pre-installed stack: nginx + Apache, PHP-FPM, MySQL/MariaDB, Sphinx, Push server. For VPS — the best start. Everything is already configured for Bitrix, including OPcache, log rotation, and firewall. Management via web panel on port 8890. Bitrix documentation recommends starting with BitrixVM for predictable performance.

VPS/VDS is the sweet spot. Minimum configuration for a medium online store: 2 vCPU, 4 GB RAM, SSD. Optimal: 4 vCPU, 8 GB RAM. OS: Ubuntu 22.04 or Debian 12. If not BitrixVM, we configure the stack manually for the task. Virtual hosting — only for business cards and landing pages. Requirements: PHP 8.0+, MySQL 5.7+ / MariaDB 10.0+, 512 MB RAM, .htaccess. 1C-Bitrix hosting partners guarantee compatibility. Dedicated server — for highload. Typical architecture: web server separate, database separate, Redis/Memcached separate. For Enterprise edition — web cluster with load balancer. Cloud (Yandex Cloud, VK Cloud, Selectel) — when load spikes: sales, seasonal peaks. Autoscaling via Managed Kubernetes or simple VM vertical scaling.

Choosing the edition is equally important. A common mistake: choosing "Small Business" for a store that grows to B2B with wholesale prices and three warehouses in six months. Upgrading to "Business" — pay the difference, data is not lost, but it's better to plan ahead. Our specialists select the edition for current tasks and with room for growth. For example, the "Business" license (about 35,000 RUB) pays off through multi-warehouse and 1C exchange, while the wrong choice can lead to a loss of up to 30,000 RUB monthly on excess resources.

What Server Settings Are Critical for 1C-Bitrix?

Web Server and PHP

nginx as reverse proxy + Apache (mod_php) or nginx + PHP-FPM directly. The second option saves memory — Apache is not needed. But some Bitrix modules use .htaccess, so for compatibility we sometimes keep Apache. nginx configuration: fastcgi_read_timeout 300 — for long operations (1C import), client_max_body_size 1024m — large file uploads. Block access to .settings.php, .settings_extra.php, bitrix/.settings.php — they contain database passwords. Rewrite rules from urlrewrite.php — Bitrix generates them, but with nginx + PHP-FPM they need to be duplicated. PHP 8.0–8.2 with extensions: mbstring, curl, gd, xml, json, opcache, redis/memcached. Key php.ini settings: opcache.memory_consumption=256, opcache.max_accelerated_files=20000, max_execution_time=300, memory_limit=512M, upload_max_filesize=100M, post_max_size=128M.

Database and Caching

MySQL/MariaDB. Key my.cnf parameters: innodb_buffer_pool_size — 70–80% RAM, innodb_log_file_size=256M, tmp_table_size=256M, max_heap_table_size=256M, thread_pool_size — number of CPU cores. Encoding utf8mb4 mandatory, otherwise emoji and special characters break. Redis is preferable to Memcached for Bitrix — supports persistent connections and is more reliable. In production, Redis handles concurrent writes three times faster than Memcached under typical load. Configure in .settings_extra.php:

'cache' => ['value' => ['type' => ['class_name' => '\\Bitrix\\Main\\Data\\CacheEngineRedis']]]
'session' => ['value' => ['mode' => 'default', 'handlers' => ['general' => ['type' => 'redis']]]]

sudo apt install redis-server
sudo systemctl enable redis

SSL, Email, and Cron

SSL — Let's Encrypt via certbot in 90% of cases. Redirect HTTP → HTTPS (301), HSTS, TLS 1.2/1.3, OCSP Stapling. In Bitrix, switch to HTTPS in the main module settings. Email: abandon mail() — connect SMTP (Yandex.Mail for domain, Mail.ru for Business). Be sure to configure SPF, DKIM, DMARC. Without SPF, emails go to spam. Test deliverability via mail-tester.com — score 9+/10. Cron: Bitrix agents switch to system cron — * * * * * /usr/bin/php /var/www/bitrix/modules/main/tools/cron_events.php. Schedule 1C exchange (15–60 min), search reindex, backups (mysqldump + rsync, rotation 7+4), temporary file cleanup.

Security and Administration

File system: owner www-data, directories 755, files 644, upload 775. nginx blocks access to configuration files. Enable Bitrix Proactive Protection — WAF, activity control (block after 5 failed attempts), kernel integrity check. For admin panel: two-factor authentication via Google Authenticator or OTP, restrict access by IP via nginx for paranoid.

How Long Does 1C-Bitrix Installation and Configuration Take?

Post-Installation Checklist

1. Performance Monitor (/bitrix/admin/perfmon_panel.php) — aim for 30+ points. Below 20 means serious configuration issues.
2. System Check — automatic check of all parameters. Red items must be fixed, yellow — case by case.
3. Security Scanner — check for typical vulnerabilities.
4. PageSpeed Insights — TTFB < 200ms on VPS, LCP < 2.5s.
5. Test 1C exchange — if integration is planned, verify CommerceML exchange before launch.

Additionally, check software versions, caching settings, cron operation, SSL certificate, SPF/DKIM/DMARC, access rights, delete default users and pages. For projects with 54-FZ, ensure fiscalization is configured via OFD provider.

Deliverables

• Fully configured server for 1C-Bitrix with MySQL, PHP, nginx optimization.
• Installed and activated license of the required edition.
• SSL certificate, email settings, cron and backups.
• Documentation: all configuration parameters, access credentials, cron tasks.
• Content manager training: how to log into admin panel, add products, upload images.
• Post-installation support for 30 days — consultations on settings.

Why Trust Professionals with Installation?

Incorrect installation means lost time and money. We've seen projects where a store on "Start" couldn't handle 50 visitors because innodb_buffer_pool_size wasn't configured. After migrating to VPS with correct configuration, the site "flew". Incorrect configuration can cost 30,000 RUB monthly due to excessive resource consumption. You get a ready-made architecture that scales. Order turnkey 1C-Bitrix installation — get a reliable platform for business growth. Contact us for a free consultation: we'll calculate the cost and time for your project. Over 7 years of experience, 120+ Bitrix projects implemented, including highload stores with million-item catalogs. Get in touch — we'll help configure Bitrix for your project.