Hello Umod Community, I'm the proud owner of a rust server but when someone joins or leaves my server there is a small lag spike is there a plugin to solve this problem or a other solution

Welcome to uMod.

What mods do you have? You can type plugins into console and paste that here with the "Insert Code Sample" button.

I would venture a guess that this is dependant on the server hardware. Are you self hosted or do you pay a server host?

Hello Ryan, thankyou for the reply my server is hosted on a kvm vps with these specs: 2 cores (3.5 ghz) - 8 gb ram ddr4,
and this are my plugins:

01 "Admin Radar" (5.0.9) by nivex (4.99s) - AdminRadar.cs
02 "Arkan" (1.0.18) by Antidote (2.58s) - Arkan.cs
03 "AutoBroadcast" (1.0.8) by Wulf/lukespragg (0.17s) - AutoBroadcast.cs
04 "Auto Commands" (2.0.1) by Wulf (7.92s) - AutoCommands.cs
05 "Auto Doors" (3.2.3) by Wulf/lukespragg/Arainrr (17.91s) - AutoDoors.cs
06 "AutoPurge" (1.6.1) by Fujikura/Norn (10.43s) - AutoPurge.cs
07 "Automatic Authorization" (1.1.12) by k1lly0u/Arainrr (16.32s) - AutomaticAuthorization.cs
08 "BGrade" (1.0.49) by Ryan (0.87s) - BGrade.cs
09 "Backpacks" (3.1.0) by LaserHydra (413.66s) - Backpacks.cs
10 "Better Chat" (5.2.5) by LaserHydra (7.30s) - BetterChat.cs
11 "Block Remover" (0.4.55) by austinv900 (15.43s) - BlockRemover.cs
12 "Rust:IO Clans" (1.7.6) by playrust.io / dcode (0.11s) - Clans.cs
13 "Dangerous Treasures" (2.1.3) by nivex (19.98s) - DangerousTreasures.cs
14 "Discord Report" (1.0.3) by Iv Misticos (0.26s) - DiscordReport.cs
15 "EasyVote" (2.0.35) by Exel80 (0.03s) - EasyVote.cs
16 "Friends" (3.1.1) by Wulf (0.08s) - Friends.cs
17 "Furnace Splitter" (2.2.4) by FastBurst (12.03s) - FurnaceSplitter.cs
18 "GUIAnnouncements" (2.0.0) by JoeSheep (12.61s) - GUIAnnouncements.cs
19 "Gather Manager" (2.2.74) by Ryan (0.24s) - GatherManager.cs
20 "Image Library" (2.0.54) by Absolut & K1lly0u (0.14s) - ImageLibrary.cs
21 "InfoPanel" (1.0.1) by Default (21.47s) - InfoPanel.cs
22 "Instant Craft" (2.1.4) by Orange (0.96s) - InstantCraft.cs
23 "Instant Gather" (1.0.6) by supreme (0.35s) - InstantGather.cs
24 "Kits" (3.2.95) by Reneb (3.86s) - Kits.cs
25 "MagicLoot" (0.1.24) by Norn / Kunazai (6.64s) - MagicLoot.cs
26 "NTeleportation" (1.3.6) by Author Nogrod, Maintainer nivex (1.79s) - NTeleportation.cs
27 "NoEscape" (2.1.24) by Calytic (24.21s) - NoEscape.cs
28 "No Give Notices" (0.3.0) by Wulf (0.00s) - NoGiveNotices.cs
29 "NoWorkbench" (0.1.51) by k1lly0u (38.42s) - NoWorkbench.cs
30 "Powerless Turrets" (3.0.3) by August (0.39s) - PowerlessTurrets.cs
31 "PrivateMessages" (1.1.11) by MisterPixie (0.00s) - PrivateMessages.cs
32 "Quick Smelt" (5.1.3) by Iv Misticos (0.75s) - QuickSmelt.cs
33 "Remover Tool" (4.3.15) by Reneb/Fuji/Arainrr (0.21s) - RemoverTool.cs
34 "SAMSiteAuth" (2.3.3) by haggbart (0.22s) - SAMSiteAuth.cs
35 "Server Armour" (0.4.96) by Pho3niX90 (4.53s) - ServerArmour.cs
36 "ServerInfo" (0.5.4) by FastBurst (0.27s) - ServerInfo.cs
37 "Sign Artist" (1.1.9) by Whispers88 (0.00s) - SignArtist.cs
38 "Simple Kill Feed" (2.0.1) by CosaNosatra (0.19s) - SimpleKillFeed.cs
39 "SkipNightUI" (0.1.2) by k1lly0u (12.83s) - SkipNightUI.cs
40 "Stack Size Controller" (2.0.3) by Canopy Sheep (0.02s) - StackSizeController.cs
41 "TimeOfDay" (2.3.4) by FuJiCuRa (0.00s) - TimeOfDay.cs
42 "Timed Events" (1.1.1) by Orange (0.69s) - TimedEvents.cs
43 "Timed Permissions" (1.5.0) by LaserHydra (0.01s) - TimedPermissions.cs
44 "Vanish" (1.3.1) by Whispers88 (8.97s) - Vanish.cs
45 "Vehicle Licence" (1.5.5) by Sorrow/TheDoc/Arainrr (28.90s) - VehicleLicence.cs
46 "ZLevels Remastered" (2.9.10) by Default (10.33s) - ZLevelsRemastered.cs
47 "ZoneManager" (3.0.13) by Reneb / Nogrod / k1lly0u (2.07s) - ZoneManager.cs

I'm not sure what's causing the lag spike. Maybe ServerArmor and Arkan are doing checks on new people.
Do the lag spikes occur for players that have joined before? Like, returning players.

I'm not a huge fan of this answer: But I think you should get better server hardware. The CPU looks good, you should have 10GB of memory. A stronger host machine would presumably fix lag issues.

Could you test with Arkan or ServerArmor unloaded? A good method to find a culprit plugin would be to unload all, then add a third back and test, add another third back and test, etc to try to identify which plugin may be causing the issue.