Will modification of one replica change other two replicas as well?
Hadoop have 3 replication factor, right ?
If I modify one replica, will the other two replicas also change or not ?
hadoop
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
add a comment |
Hadoop have 3 replication factor, right ?
If I modify one replica, will the other two replicas also change or not ?
hadoop
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
add a comment |
Hadoop have 3 replication factor, right ?
If I modify one replica, will the other two replicas also change or not ?
hadoop
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
Hadoop have 3 replication factor, right ?
If I modify one replica, will the other two replicas also change or not ?
hadoop
hadoop
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
edited Nov 15 '18 at 22:42
cricket_007
83k1145113
83k1145113
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
asked Nov 15 '18 at 12:03
Syed Furquan AliSyed Furquan Ali
11
11
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
But you can't modify the contents of file on hadoop because it is 'write once read many'.So,you first modify it locally and then replicate it on hdfs.So,then the contents of 3 replication are same.
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS@cricket_007.
– code_cody97
Nov 16 '18 at 10:09
add a comment |
By default, HDFS uses a replication factor equal to 3 but it can be changed. HDFS does not allow to alter just one copy of your data block, because block replication should be transparent for the user.
Technically, you can alter one copy by accessing the local file system of a single datanode, and alter the files under the dfs.datanode.data.dir local direcory, but HDFS is not aware of this change, therfore it will not be replicated for the other copies.
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53319101%2fwill-modification-of-one-replica-change-other-two-replicas-as-well%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
But you can't modify the contents of file on hadoop because it is 'write once read many'.So,you first modify it locally and then replicate it on hdfs.So,then the contents of 3 replication are same.
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS@cricket_007.
– code_cody97
Nov 16 '18 at 10:09
add a comment |
But you can't modify the contents of file on hadoop because it is 'write once read many'.So,you first modify it locally and then replicate it on hdfs.So,then the contents of 3 replication are same.
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS@cricket_007.
– code_cody97
Nov 16 '18 at 10:09
add a comment |
But you can't modify the contents of file on hadoop because it is 'write once read many'.So,you first modify it locally and then replicate it on hdfs.So,then the contents of 3 replication are same.
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
But you can't modify the contents of file on hadoop because it is 'write once read many'.So,you first modify it locally and then replicate it on hdfs.So,then the contents of 3 replication are same.
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
answered Nov 15 '18 at 14:50
code_cody97code_cody97
809
809
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS@cricket_007.
– code_cody97
Nov 16 '18 at 10:09
add a comment |
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS@cricket_007.
– code_cody97
Nov 16 '18 at 10:09
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
In other words, you "overwrite" the file on HDFS with the local edits
– cricket_007
Nov 15 '18 at 22:43
is there any way to overcome "overwrite" the file on HDFS
@cricket_007.– code_cody97
Nov 16 '18 at 10:09
is there any way to overcome "overwrite" the file on HDFS
@cricket_007.– code_cody97
Nov 16 '18 at 10:09
add a comment |
By default, HDFS uses a replication factor equal to 3 but it can be changed. HDFS does not allow to alter just one copy of your data block, because block replication should be transparent for the user.
Technically, you can alter one copy by accessing the local file system of a single datanode, and alter the files under the dfs.datanode.data.dir local direcory, but HDFS is not aware of this change, therfore it will not be replicated for the other copies.
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
add a comment |
By default, HDFS uses a replication factor equal to 3 but it can be changed. HDFS does not allow to alter just one copy of your data block, because block replication should be transparent for the user.
Technically, you can alter one copy by accessing the local file system of a single datanode, and alter the files under the dfs.datanode.data.dir local direcory, but HDFS is not aware of this change, therfore it will not be replicated for the other copies.
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
add a comment |
By default, HDFS uses a replication factor equal to 3 but it can be changed. HDFS does not allow to alter just one copy of your data block, because block replication should be transparent for the user.
Technically, you can alter one copy by accessing the local file system of a single datanode, and alter the files under the dfs.datanode.data.dir local direcory, but HDFS is not aware of this change, therfore it will not be replicated for the other copies.
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
By default, HDFS uses a replication factor equal to 3 but it can be changed. HDFS does not allow to alter just one copy of your data block, because block replication should be transparent for the user.
Technically, you can alter one copy by accessing the local file system of a single datanode, and alter the files under the dfs.datanode.data.dir local direcory, but HDFS is not aware of this change, therfore it will not be replicated for the other copies.
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
answered Nov 15 '18 at 16:09
54l3d54l3d
3,15521538
3,15521538
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53319101%2fwill-modification-of-one-replica-change-other-two-replicas-as-well%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
