Limit for user

domain

In this field, we need to name whom we are going to limit. The following can be values of this field...

type

In this field, we mention which type of limits we are going to apply to the mentioned domain. This field has two values, soft or hard...

item

This field mentions which resource we are going to limit for the mentioned domain. Here are some values for this field...

value

This field stores the values for the mentioned limit....

Limit for user

Now let’s see how we can limit the user by using the limits.conf file. We are going to understand this by taking an example. So to limit users, we need to mention username as a domain field. In this example, GFG is the user. After that we have to mention the type of limit, in this example, we set hard type. Now to set items first we are needed to choose any item from the available item so in this example, we have chosen to use CPU item. Now we have to mention value the value of item CPU is must be in minutes, so for this example let’s mention the value as 10 minutes. Here is our limit :...

Limit for Group

To limit the group we can use the same format and value used for value and item but instead of username mention the group name. Here is one example with employee group...

Using wildcards to apply limits

We had seen the one domain as the * (asterisk). To apply the limit to the whole system, we can use this wildcard domain. Here is an example with a wildcard to apply limited number of logins on the system....

Specify User ID Range For Limit

When we want to specify one limit to the multiple users, but the users do not belong to the same group, we can specify the range of the user for which the limit has to apply. When we mention the user ID range, then the mentioned limit is applied to user IDs that belong to that range. To specify the range, use : operation. Here is an example:...

Specify Group ID Range For Limit

Same as for user IDs, when we have to apply the same limit to multiple group IDs we can specify the range of group IDs. Use the : operator to mention the range....

Limit Number of Process

Now let’s explore more items than mentioned above list. There is one item called nproc by using this option we can limit the number for the user or group ID. So limit the number of processes for user gfg use the following limit....

Limit CPU Time

There is another item called cpu which is used to limit the CPU time for the mentioned user or group. So to limit the CPU time 1000 cycle to user gfg uses the following limit:...

Limit Number Of Open File

nofile is an item by using which we can limit the maximum number of files that can be opened by the user. So to limit the maximum 227 number of files that can be opened by user gfg use the following limit...

Limit Number Of Logins

By default, systems allow us to unlimited logins on the system, but it can create a security issue. So to avoid the security issue, we can limit the number of logins of the user or group of users. We can use maxlogins item to limit the number of logins of users of groups to the system. So to limit 10 logins by the user group gfg, we can use the following limit:...

Limit Number Of System Logins

In the previous example, we see how we can limit the number of logins of the user group to the system. Now to limit the maximum number of logins to the whole system we can use maxsyslogins item. So to limit 50 maximum number of logins to the system use the following  limit:...

Limit Maximum File Size

We can limit the file size of the file by using the fsize item. This limit can be useful to restrict temp or similar usage type files. So to limit gfg having a single file size of 4 GB we can use the following limit:...