diff --git a/containers/Dockerfile.EESSI-build-node-debian10 b/containers/Dockerfile.EESSI-build-node-debian10
index 6740d8c3..52e5999b 100644
--- a/containers/Dockerfile.EESSI-build-node-debian10
+++ b/containers/Dockerfile.EESSI-build-node-debian10
@@ -14,7 +14,7 @@ ARG awscliversion
 COPY --from=prepare-deb /root/deb /root/deb
 
 RUN apt-get update
-RUN apt-get install -y sudo vim openssh-client gawk autofs curl attr uuid fuse3 libfuse2 psmisc gdb uuid-dev
+RUN apt-get install -y sudo vim openssh-client gawk autofs curl attr uuid fuse3 libfuse2 psmisc gdb uuid-dev lsof
 # python3 and jq are required for eessi-upload-to-staging script (next to awscli)
 RUN apt-get install -y python3-pip jq
 RUN dpkg -i /root/deb/cvmfs_${cvmfsversion}~1+debian10_$(dpkg --print-architecture).deb \
diff --git a/containers/Dockerfile.EESSI-client-pilot-centos7 b/containers/Dockerfile.EESSI-client-pilot-centos7
index dec45083..40097d22 100644
--- a/containers/Dockerfile.EESSI-client-pilot-centos7
+++ b/containers/Dockerfile.EESSI-client-pilot-centos7
@@ -24,7 +24,7 @@ ARG cvmfsversion
 COPY --from=prepare-rpm /root/rpmbuild/RPMS /root/rpmbuild/RPMS
 COPY --from=build-fuse-overlayfs /usr/local/bin/fuse-overlayfs /usr/local/bin/fuse-overlayfs
 
-RUN yum install -y sudo vim openssh-clients
+RUN yum install -y sudo vim openssh-clients lsof
 RUN yum install -y /root/rpmbuild/RPMS/$(uname -m)/cvmfs-${cvmfsversion}-1.el7.$(uname -m).rpm \
                    /root/rpmbuild/RPMS/$(uname -m)/cvmfs-fuse3-${cvmfsversion}-1.el7.$(uname -m).rpm \
                    http://ecsft.cern.ch/dist/cvmfs/cvmfs-config/cvmfs-config-default-latest.noarch.rpm