Free tools Windows power users keep installed
One-click scans. No signup required.
Configure one Ubuntu Redis node as the primary and another as its replica by setting replicaof on the replica, supplying matching authentication, and then checking synchronization with INFO replication and ROLE. Redis replication is asynchronous and keeps a second copy current, but it does not elect a replacement primary. If you need automatic failover, add Sentinel or another high-availability system.
Need a server to try this on? Antihost offers Linux VPS plans with NVMe storage, full root access and a 14-day free trial.
What Redis replication does—and what it does not do
Redis uses a primary-replica model. Clients normally send writes to the primary, which streams the resulting write effects to one or more replicas. Expirations and evictions are propagated as well. Replication is asynchronous by default, so a replica can briefly lag while data is transferred or while the network is busy.
As an Amazon Associate I earn from qualifying purchases.
A replica reconnects after a short interruption and may perform a partial resynchronization instead of receiving the entire dataset again. That recovery depends on the primary retaining the required replication history in its backlog and on the replica still having a compatible replication state.
- Replicas are read-only by default.
- Replication copies data; it is not a backup strategy by itself.
- Replication does not perform leader election or automatic promotion.
REPLICAOF NO ONEis a manual promotion command.
Use replication when you need a current read copy, a standby node, or a building block for high availability. Add Sentinel or another HA layer when the system must select and promote a new primary without an operator.
#1 Best Overall
- BLUE LIGHT BLOCKING GLASSES: Our blue light glasses for women boast UV400 protection, blocking harmful blue rays from computer screens. With these bluelight glasses women, you can enjoy gaming, reading, or watching TV with no worries of eye strain.
- EYE RELIEF: Our blue light glasses are engineered to reduce blurry vision or strain caused by prolonged screen time. These womens blue light glasses aid in better sleep by preventing blue light from disrupting your natural sleep cycle, helping you fall asleep faster and enjoy a more restful night's sleep, making them the perfect christmas present.
- COMFORTABLE: Crafted from durable material, our trendy blue light glasses for woman or blue light glasses men ensure long-lasting comfort. The high-transmittance lenses accessories, gamer gifts for men, help keep your eyes relaxed. Perfect stocking stuffers, gifts for gamers men, christmas gifts for men, halloween costumes.
- LIGHTWEIGHT: These clear blue light glasses feature a lightweight frame, meaning they’ll stay comfy for long-term wear. Perfect as blue blockers glasses for women or mens blue light glasses, these non-prescription fake glasses for men can be worn throughout the day. The blue light blocking glasses women feature polycarbonate HD lenses, which are anti-reflective and restore true color.
- WORRY-FREE PURCHASE: If you experience any issues, our support team is ready to assist you quickly. These are the perfect costume glasses for cosplay dressing up.
Plan the Ubuntu nodes and network first
Choose primary and replica addresses
Record the private address and Redis port for each machine before editing configuration. In the examples below, replace the conceptual values with addresses that are routable between the two nodes:
| Role | Example address | Purpose |
|---|---|---|
| Primary | 10.0.0.10 |
Accepts writes and streams changes |
| Replica | 10.0.0.11 |
Receives the primary’s stream and serves reads |
| Redis port | 6379 |
Default TCP port unless your installation uses another value |
Do not expose Redis broadly to the internet. Permit TCP 6379 only from the application, administration, and replication networks that genuinely need it. The exact firewall command depends on your Ubuntu release and firewall policy; the important requirement is that the replica can reach the primary’s configured address and port while untrusted sources cannot.
Do these 3 things before closing this tab:
1Fix the driver behind crashes, sound loss and screen glitches2Repair Windows errors before they cause bigger problems3Scan for outdated or missing drivers - takes under a minuteCheck the package and service layout
Ubuntu Redis packages can differ in configuration-file paths, service-unit names, and whether a deployment uses a distribution package or a separately installed Redis build. Identify the configuration file used by the running process and the service unit before making changes. On many Ubuntu package installations the unit is named redis-server, but do not assume that name for a custom installation.
- Confirm the installed Redis version on both nodes; ACL behavior and TLS options depend on the version.
- Confirm which process owns port 6379 and which configuration file it loaded.
- Keep a copy of the current configuration before editing it.
- Plan a maintenance window if changing bind addresses or authentication on a live primary.
Configure the primary Redis server
Bind Redis to a private interface
Open the primary’s active redis.conf and bind Redis to its private address plus localhost. Keep protected-mode yes unless you have a controlled, authenticated design that requires another setting.
bind 10.0.0.10 127.0.0.1
protected-mode yesUse the actual private address of the primary, not the example address. A bind address that is not present on the host, or a firewall that blocks the replica, will leave the replica unable to connect.
Choose authentication
For legacy password authentication, set a long, unique secret on the primary:
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
requirepass <long-primary-secret>Do not paste a real secret into shell history, tickets, or public configuration examples. Protect the configuration file itself because it contains the credential.
Redis 6 and later support ACL users. A stronger design is to keep the default user policy deliberate and create a dedicated replication identity with only the permissions required by replication. Configure that identity with masteruser and its secret on the replica. The exact permission set must match the Redis version and the replication commands it requires; test the account before removing broader permissions.
Rank #2
- WINDEX GAMING WIPES: effortlessly clean all your gaming gear and gaming electronics in one easy step with our new Windex Gaming Wipes
- AMMONIA FREE: our ammonia-free formula is safe to use on all of your favorite gaming equipment like consoles, headsets, controllers, screens, keyboards, and more
- PRE-MOISTENED WIPES: each wipe instantly removes dust, dirt, and stubborn smudges and fingerprints leaving a streak-free shine
- ANTI-STATIC: great for cleaning and wiping down your gaming gear and electronics leaving behind no visible residue
- COMPACT RESEALABLE PACKAGE: store your pack of Windex Gaming Wipes anywhere in your home for whenever a quick and easy wipedown is needed
Keep the primary’s role unambiguous
The primary should not contain a stale replicaof directive from an earlier topology. After editing, inspect the effective configuration and later confirm the role with ROLE and INFO replication.
Configure the replica
Point it at the primary
On the replica, edit its active configuration file and add the primary address and port:
Quick wins for a faster PC:
Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →replicaof 10.0.0.10 6379The equivalent runtime command is:
REPLICAOF 10.0.0.10 6379The configuration-file form survives a restart. A runtime command changes the running instance immediately but must also be written to the configuration if you want the relationship to return after a reboot.
Supply the primary’s credentials
If the primary uses requirepass, add the same secret to the replica configuration:
masterauth <long-primary-secret>When the primary uses ACLs, configure both the replication username and its secret instead of relying on the default user:
masteruser <replication-user>
masterauth <replication-user-secret>Ensure that the account is permitted to perform the replication handshake and synchronization operations required by your installed Redis release. A valid password with insufficient ACL permissions produces an authentication or authorization failure that looks similar to a connectivity problem until you inspect the logs.
Retain the read-only safeguard
Replicas are read-only by default. Leave that behavior enabled unless you have a narrowly justified operational reason to change it. A write accepted locally on a writable replica can diverge from the primary and later be overwritten or create inconsistent application results.
Apply the configuration safely
Restart or reload through the installed service
Use the service-management procedure supplied by your Ubuntu package or deployment. On installations that provide the conventional unit, the restart is commonly:
Rank #3
- Ergonomic & Adjustable Design: Fight "text neck" and improve your posture. Designed for comfort, it offers an adjustable height (7.1in-8.5in) (1.4in adjustable range) and angle (5°-85°) Please note: cell phone stand is only 9 inches tall—the length of a standard pencil
- Without blocking subtitles Perfect for office desk Tiktok Face Time Zoom video—this is the ultimate kitchen desk essential for phones! Perfect viewing experience while reducing neck back strain, A must-have for gamers streamers desk, and anyone who values both style and support!
- Sleek & Stable Design fits Otterbox Case: Say goodbye to bent cables, tangles, and tip-overs! LISEN’s stylish adjustable desk phone holder features a built-in charging hole and smart cable management, keeping your phone secure and your workspace clutter-free cool gadgets for men
- ANTI-SLIP DESIGN free hands: The under 10.00 items easy gadgets back and the bottom of this kitchen essentials for women are fully covered by anti-skid silicone, which LISEN stand up desk decor can provide maximum protection device from any scratches and slides
- Your Perfect Viewing Companion:If your product arrives damaged or breaks within 365 days, reach out to LISEN for a quick and hassle-free solution. Struggling with assembly, like tightening the screw? We’ve got your back! Your experience matters to us. (Product including: phone Holder stand*1, screw*1, hexagon screwdriver*1, specification*1)
sudo systemctl restart redis-server
sudo systemctl status redis-serverIf your unit has another name, substitute that unit. A restart is appropriate for settings that are read only at startup. Some parameters can be changed without a restart, but changing a bind address or authentication policy can interrupt clients, so schedule it deliberately.
Use runtime changes for controlled tests
For a live diagnostic or a topology change, an authenticated administrator can use CONFIG SET for settings that support it and REPLICAOF to attach a replica. Runtime changes are not a substitute for editing the file: persist the final values or a later restart will discard them.
When changing an existing replica to a different primary, check the dataset and application impact first. The new synchronization can replace the replica’s local dataset with the primary’s dataset.
Verify that synchronization is working
Inspect replication status on both nodes
Connect with an authenticated administrative client and run:
redis-cli -h 10.0.0.10 -p 6379 INFO replication
redis-cli -h 10.0.0.11 -p 6379 INFO replication
redis-cli -h 10.0.0.10 -p 6379 ROLE
redis-cli -h 10.0.0.11 -p 6379 ROLEDo not put production passwords directly in a command line that will be saved in shell history. Authenticate interactively or use your organization’s approved secret-delivery method.
On the primary, INFO replication should identify a primary role and show connected replicas. On the replica, inspect the reported primary address, link status, synchronization state, and replication offsets. The exact field set varies by Redis version, so focus on whether the link is established and whether offsets advance rather than relying on one field name alone.
Windows Errors? Fix Them Before They Spread
Repair common Windows errors and clear accumulated junk for a smoother, more stable PC - no reinstall needed.Free scan · no reinstallCrashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteROLE provides an independent role check. It should report the primary role on the writer and the replica role, primary address, and offset information on the reader.
Perform a disposable end-to-end test
- Choose a key name that cannot collide with application data, such as
replication-check-2026-10-15. - Write it to the primary with a short expiration so the test cannot accumulate indefinitely.
- Read the key from the replica. Because replication is asynchronous, retry after a short interval if the first read occurs before the stream is applied.
- Confirm that the key expires on the replica as the primary’s expiration event is propagated.
- Delete any test data that remains and record the observed link status and offsets.
Never use a production key for this check, and never test by writing to the replica while it is intended to remain read-only.
Rank #4
- Easy Installation: Our gaming lights have been designed to enhance your entertainment experience. Simply position the led light bar next to your TV or game console to create a game room environment with ease. They come with USB power and a 60 inch cord for direct mounting and mobility
- Audio Syncing & Extensive Mode: The built-in high-sensitivity music sensor allows you to sync the TV led lights to your favorite music. Lights react and move to the beat of music, film and game audio, creating an incredible immersive sound and light experience – and all without the need for an additional hub. You can choose from 64+ patterns, including strobe, illusion, jump, energy, gradient, running, chasing, fluttering mode etc. Each mode can be applied to different scenes
- 64+ Chasing IC+RGB & W Effect: The independent control design of IC+RGB and white all-in-one multifunctional rgbw led bar lights monitor backlight allows you to easily switch the led lights for desk between IC+RGB and white to enjoy a variety of lighting effects, you can choose white lighting mode with high brightness for better illumination when working, etc. Choose IC+RGB lighting mode when you need to create an entertaining atmosphere for the light show, 16 million colours of Color changing rgb light bar let you dance to the beat and create a dynamic party atmosphere
- Dynamic and Dimmable Lights: 1%-full brightness free brightness adjustment gives you the flexibility to adjust dimmable led light bar for room decorations or a variety of occasions
- USB Powered: USB light bars for room can be powered by powernank, usb charger, TV, Monitor, laptop PC mainframe, making behind TV led lighting bar easy to install in any location.TV led lights are powered by the TV usb interface / PC mainframe, can be turned on/off synchronously with TV / PC
Read the logs when status is ambiguous
Redis logs identify connection retries, authentication failures, full synchronization, and partial resynchronization attempts. Review the service journal or the log destination configured by your installation on both nodes. Correlate the timestamp with firewall changes and primary restarts; a replica can report a transient state during an expected restart.
Troubleshoot a replica stuck in CONNECTING
1. Separate reachability from authentication
From the replica host, first verify that the primary address resolves to the intended private interface and that TCP 6379 is reachable. If the connection cannot be opened, inspect the primary’s bind setting, host firewall, cloud network ACLs, security groups, and the port configured in both files.
Recommended Free Tools
If TCP reaches Redis but the link fails during the handshake, compare the primary’s requirepass or ACL policy with the replica’s masterauth and, when applicable, masteruser. Check for a typo, an expired secret, or a replication account that lacks required permissions.
2. Check protected mode and address selection
Protected mode is intended to prevent unsafe exposure. A private, authenticated, correctly bound deployment should satisfy its safety assumptions. Do not “fix” a connection by exposing Redis publicly or disabling protections without documenting the network and authentication controls that replace them.
3. Investigate stale or repeatedly interrupted links
After a brief outage, Redis may attempt partial resynchronization. If the replica repeatedly falls back to a full synchronization, examine network stability and the primary’s replication backlog sizing. The backlog must retain enough history to cover the interruption; otherwise the replica must receive the dataset again.
Also check CPU, memory, disk activity, and persistence load on both nodes. A saturated primary can delay replication even when the network is healthy. Compare offsets over time instead of treating one instantaneous lag value as a failure.
4. Resolve writes appearing on the replica
Check whether replica-read-only was intentionally disabled and whether an administrator used a write-capable connection against the replica. Re-enable read-only behavior unless the exception is explicitly required, then reconcile any data written locally with the primary before trusting the replica again.
5. Do not mistake normal synchronization for failure
A newly attached replica can spend time loading the initial dataset. During that period, status fields may show synchronization in progress and the replica may not yet be suitable for reads. Wait for the initial transfer to finish, then verify advancing offsets and a healthy link.
Best Value
- Compatible with Wide Screens - To ensure compatibility with the dual monitor mount, your each monitor must meet three conditions at the same time: First, computer screens size range: 13 to 32 inches. Second, screen weight range: 4.4 to 19.8 lbs. Third, the back of the monitor screen must have VESA mounting holes with a pitch of 75x75mm or 100x100mm.
- Regarding the compatibility with desks - Your desk must meet three conditions at the same time: First, desk material: Only wooden desks are recommended, plastic or glass desks cannot be used. Second, desk thickness range: 0.59" - 3.54". Third, the bottom of the desk should not have any cross beams or panels, as this will interfere with installation. We recommend carefully checking that your desk and monitors meets all above conditions before purchasing.
- Dual C-Clamp Hold - Worried your dual monitors might wobble or slip? Our upgraded base uses a larger platform plus a dual C-clamp structure to lock the dual monitor arm firmly to your desk. Each arm safely keeps your screens steady while you type, click and game—no shaking, no sliding, just a clean and secure setup you can trust every day. It also provides Grommet Mounting installation choice, both options ensure stable and secure fixation for your 0.59" - 3.54" desk.
- Full-Motion Adjustment For Comfortable View - Pull the screen closer when you’re deep in a spreadsheet, push it back to watch videos, or rotate to portrait for coding — moving everything smoothly with just one hand. The monitor stand offers +85°/-50° tilt, ±90° swivel and 360° rotation. Raise your monitor up to 15.75″ to support a healthy sitting posture. Whether you’re working from home, gaming through the night, or switching between video calls and documents, getting the screens to your natural line of sight helps relieve neck, shoulder and back strain so you can stay focused longer with less fatigue.
- Keep Your Desk Organized: By lifting both screens off the desktop, this dual monitor stand opens up valuable space for your keyboard, notebook, docking station or a simple, clutter-free work area. Built-in cable management guides wires along the arms, keeping cords out of sight and out of the way. Enjoy a tidy, modern workstation that looks as good as it feels to use.
Protect replication traffic
Password and ACL authentication
Password authentication prevents unauthenticated commands but does not conceal the credential in transit. Redis documentation notes that the AUTH command, like other Redis commands, is sent unencrypted unless the connection is protected. Use private networks at minimum and ACL users with least privilege where your Redis version supports them.
TLS for client and replication channels
Redis supports TLS for client and replication connections. On the replica, tls-replication yes enables TLS for its outgoing replication connection:
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →tls-replication yesTLS is only complete when both ends are configured consistently. Install certificates and private keys securely, configure the trusted certificate authority, and apply hostname or identity verification appropriate to your certificate design. Test the TLS connection before switching a production replica, and ensure clients use the matching TLS port and settings.
Keep certificate rotation in your operational runbook. A replica that cannot validate a renewed certificate will disconnect even though its Redis credentials and firewall rules remain correct.
Replication is not automatic failover
Manual promotion
If the primary is unavailable and you have confirmed that the replica contains the data you want to serve, an operator can promote it with:
REPLICAOF NO ONEThis stops replication and leaves the replica’s current dataset in place. Redirect clients to the promoted node, update the topology, and decide how the former primary will be reintroduced. Promotion can lose the most recent writes that had not reached the replica because replication is asynchronous.
Monitored promotion with Sentinel
For automatic failover, deploy Redis Sentinel or another HA system. Sentinel monitors Redis instances, coordinates a quorum, and can promote a suitable replica. Authentication must be configured for Sentinel-to-Redis communication and for clients that discover the current primary. Test split-brain prevention, quorum behavior, notification handling, and client reconnection before relying on unattended promotion.
Choose the operating model
| Deployment choice | Operational effort | Failover behavior | Security and control | Recovery characteristics |
|---|---|---|---|---|
| Manual replication on Ubuntu | You maintain packages, configuration, firewall rules, monitoring, certificates, and promotion procedures on each node. | Promotion is manual with REPLICAOF NO ONE. |
Maximum control over bind addresses, ACLs, TLS, and OS policy; you are responsible for getting each right. | Automatic reconnect and possible partial resynchronization; backlog and network stability determine whether a full sync is needed. |
| Ubuntu nodes with Sentinel | Additional Sentinel processes, quorum design, authentication, monitoring, and client discovery configuration. | Monitored promotion can occur without a human when quorum and health conditions are met. | You retain host-level control while adding HA configuration and more moving parts. | Still depends on asynchronous replication and a sufficiently current replica. |
| Managed Redis service | The provider handles much of the node maintenance; you configure access, clients, and service-level policies. | Depends on the provider’s documented HA design and plan. | Less host-level control, with provider-specific networking, ACL, TLS, backup, and compliance options. | Depends on the service’s replication, backup, and recovery guarantees; verify them before migrating. |
Choose manual replication when you need direct Ubuntu and Redis control and can staff the operational work. Choose Sentinel or a managed service when the cost of delayed human promotion is higher than the added complexity or service cost.
Operational checks after setup
- Alert when the replica link is down, synchronization remains in progress unexpectedly, or offsets stop advancing.
- Monitor the primary’s replication backlog and memory headroom; a backlog that is too small for normal outages forces expensive full synchronizations.
- Keep the replica’s read-only setting and authentication policy under configuration management.
- Test a planned promotion and a return-to-service procedure, not only the initial synchronization.
- Document which clients read from the replica and how they discover the current primary after failover.
- Review firewall rules and TLS certificate expiry as part of routine maintenance.
- Use backups or snapshots for recovery from deletion, corruption, or an error replicated to every node; replication alone reproduces such mistakes.
Once the primary reports a healthy replica, the replica reports an established link, offsets advance after a test write, and your promotion procedure is documented, the Ubuntu replication configuration is complete. The remaining work is operating it: monitoring lag, protecting credentials and traffic, sizing the backlog, and rehearsing the failure path you actually intend to use.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
